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MSC.Nastran 2005 - MSC Software Corporation

1. ES 9 81 aire EOE DUI MEL Aeon EUR nen Lima ud b m s EF Ir UR T Ted Leite fu jp s e TENA CHAPTER 2 29 Nonlinear Analysis MEC 81 TOR 15 TEM E _ meam 901 IBads Femmes Be rior 05 LIIS mamii Portions the MSC Nastran input file named projtl dat are shown and discussed below SOL 700 NLTRAN path 1 stop 1 TIME 10000 CEND ECHO NONE DISPLACEMENT SORT1 print PLOT ALL Stress 5 1 ALL Strain SORT1 PLOT ALL accel print plot ALL velocity print plot ALL echo both SPC 2 1 5 20 1 weightcheck yes page BEGIN BULK TSTEPNL 20 10 11 1 5 10 30 PARAM DYD DYCONSLSFAC 1 0 PARAM OGE PARAM AUTOSPC YES PARAM GRD param dyendtim 1 TOUT 5 OM NO PNT 0 param 51 1 param dyl BCTABLE 5 BCBODY BCBODY 5 BCPROP BCPROP PSOLID 5 5 5 PSOLID 5 5 5 5 5 5 ENDDATA dknd 0 T SLAVE MASTER 4 YES DEFORM 3 0 DEFORM 4 0 Material MAT PLASTIC KINE 2 id 2 18 62 1 17 622 020179 Material MAT PLASTIC 1 id 1 7 896 2 1 284 0 01 1 1 0 1246 1 3 0 03339 2586 2586 CHAPTER 2 31 Nonlinear Analysis All of the previous
2. post tocase subc2 OUTPUT POST SET 1 ALL SURFACE 1 BEGIN BULK GRID 1 ET 1 QUADR ELI subcase 1 QUADR ELI subcase S TO SEPARATE SUBCASE FILES FIBRE Z1 04 EMENTS MEMBRANE EMENTS BENDING 2 SYSTEM BASIC NORMAL 2 TOPOLOGICAL 02 240 PC PC PC PC PC 0 ES O 9 UO END DATA BW owe WD tr 100 100 N NNN NNN NY NH NEWSEQ 100 100 100 100 100 100 1 6 1 mn 18 16 08 24 24 GO OI ON OD 001 B CO B 0 GR CO GR 03 08 08 12 12 nd e e 225 4 4 poa 6 4 N 88 5 2 4 04 5 4 4 2 6 2 PAN OF 0 PN 199 66 4 OT BD NNN 123456 123456 123456 123456 NBN S 2 44 owed SOSS CHAPTER 1 0 Upward Compatibility DMAP Modules in MSC Nastran 2005 B Summary of Data Block Changes from MSC Nastran 2004 to MSC Nastran 2005 More Stringent Case Control Check a 10 1 DMAP Modules in MSC Nastran 2005 This section summarizes DMAP module changes from MSC Nastran 2004 to MSC Nastran 2005 which could affect user DMAP alters and solution sequences This information is intended to help convert MSC Nastran 2004 DMAP alters
3. assigns the file d1 f11 to be the DDAM output which will be used as the input to the Fortran program The DELETE qualifier tells MSC Nastran to delete any existing versions of the file and replace them with the one generated in this submittal The output file from the Fortran program must be assigned as well ASSIGN INPUTT4 2 d1 f13 UNIT 13 FORM FORMATTED DEFER DEFER tells MSC Nastran not to check for the existence of the file or delete an existing one Finally in SOL 187 the execution of the Fortran program is directed by a control file that must be created and identified ASSIGN INPUTT4 dl ddd UNIT 21 FORM FORMATTED The format of this file will be discussed later 160 Case Control Data The required Case Control is similar to that required for a SOL 103 modal run with a few caveats and exceptions The METHOD command for the residual structure will determine the frequency range of the dynamic response calculations used by DDAM Because of this be sure to include a broad enough range to ensure that the required modal mass will be available for processing All procedures affecting Superelement reduction to the residual degrees of freedom are allowed i e component mode synthesis GDR and Guyan reduction However NRL summed results can only be generated for the residual model A PARAM POST can be used with a limited number of output requests to generate data for post processing Case co
4. Introduction 96 Benefits 96 5 Dynamic Analysis 6 Optimization Inputs and Outputs 96 Guidelines 97 C Set Improvements 102 Enhancements to the MODESELECT Case Control Command 103 m Automatic Q Set AUTOOSET 105 Example 106 m Enhancements to Dynamic Excitation Processing in DPD Module 109 m Enhancements to Transient Response Analysis 110 Increased Accuracy from TRLG Module 110 Improved Calculations for Enforced Motion in TRLG and TRD1 Modules 110 a Initial Condition Specification for Enforced Motion Usage via SPC SPCD 110 Composite Ply Strength Ratio Response Type for the DRESP1 Entry 114 Introduction 114 Benefits 114 Input 114 Outputs 114 Guidelines and Limitations 115 Example TPL csrsens dat 115 m New FUNC tions for the DRESP2 Entry 117 Introduction 117 Benefits 117 Theory 117 Input 119 Outputs 120 Guidelines and Limitations 120 m Transformation of Approximate Optimization Task to a Feasible Design 122 Introduction 122 Benefits 122 Theory 122 Input 123 Outputs 123 Guidelines and Limitations 123 Example TPL mmfdpen dat 123 m Residual Vectors Based on Adjoint Loads 125 Introduction 125 Benefits 125 Input 125 Outputs 125 Guidelines and Limitations 125 Example rvadjsens dat 126 Multiple Boundary Conditions for DFREQ MFREQ in SOL 200 128
5. DDAM with SOL 187 The first step of the procedure is the calculation of the modal frequencies and participation factors that are accomplished in MSC Nastran by SOL 187 The model must be in a free free condition with the foundation degrees of freedom referenced by a SUPORT entry The DDAM processor considers the SUPORTed degrees of freedom and any other grids rigidly connected to them to be a fixed base for the CHAPTER 8 159 DDAM Processor modal analysis The information needed for the Fortran program is output from MSC Nastran to unit 11 in ASCII format Unit 11 will be assigned to a file using the ASSIGN statement in MSC Nastran The following paragraphs describe the Executive Case Control and Bulk Data Sections of the MSC Nastran necessary Executive Control Data File Management Section The solution sequence must be SOL 187 For example SOL 187 It is necessary to include ASSIGN statements to assign the plot output and DDAM output to physical files For example ASSIGN OUTPUT2 dl opw UNIT 34 DELETE assigns OP2 formatted post processing data to be sent to the file dl opw You also need to assign the NRL summed plot data to separate units ASSIGN OUTPUT2 dl opx UNIT 31 DELETE ASSIGN OUTPUT2 dl opy UNIT 32 DELETE ASSIGN OUTPUT2 dl opz UNIT 33 DELE The following ASSIGN OUTPUT4 d1 f 11 UNIT 11 FORM FORMATTED DELETE
6. If a POST command is present within any subcase a POST command must also be present above the subcase level The placement of the POST command above the subcase level causes a cumulative effect on POST commands in subsequent subcases Any options specified above the subcase level propagate down into the POST command within a subsequent subcase Thus if a POST command specifies NODISP no displacement output wanted above the subcase level then a POST command with the DISP option would be required within a subcase to generate any output to the OUTPUT file for displacements This also implies that changing the OUTPUT file unit reference number with the TOFILE option in subcase causes all output quantities currently scheduled for output to be switched to the new unit number not just those in the oplist for the current POST command When the name of an output file is specified by keyword TOFILE the ASSIGN statement in the File Management Section FMS can be used to specify the full path of its root name the logical key word for the root name is OUTPUT2F The default root name is the MSC Nastran job name FORTRAN unit reference number 19 has been reserved by MSC Nastran for OUTPUT2F although the user can assign other FORTRAN unit number to it The full file name is in the form of root name suffix filename When the name of an output file is specified by keyword TOCASE the ASSIGN statement in the File Management Section FMS
7. Improved Parallel Processing for SOL 600 39 Pre release of the Nonlinear Transient Analysis in SOL 400 43 Introduction 43 Benefits 43 Limitations for the Current Release 44 Case Control Commands SUBCASE STEP and ANALYSIS 45 Vector Operations and Convergence Criteria 47 Solution Algorithm and Simulation of SOL 129 47 3 Numeric Enhancements 4 Elements a Nonlinear Iteration Summary Table for Nonlinear Transient Analysis in SOL 400 48 Restart 50 Temperature Excitation 51 Outputs 52 User Interfaces 53 Examples 55 Correction in the Solution Algorithm for Elasto Plastic Material 67 Example 68 Correction for the Nonlinear Element Strain Energy 70 Example 70 m ACMS Now Available in the Matrix DOF Domain 74 Improvements for Geometric Domain Based ACMS 76 Improved Matrix Diagonal Diagnostics for 2x2 Pivots MAXRATIO 77 m Performance Improvement in Modal Frequency Response for Large Frequency Ranges 78 m Temperature Dependent Composites Support Extended to Unsymmetric Laminates 80 Global Ply Results Tracking 83 m GPFORCE and ESE Output for DMIG and GENEL 87 Bar Element Torsional Mass Moment of Inertia 88 PARAM COUPMASS Lumped Mass Option 89 Inputs 89 Outputs 89 m QUADR Convergence Behavior 92 Introduction 92 Benefits 92 Inputs 92 Example 92 m Arbitrary Beam Cross Section Pre Release 96
8. TheSRCOMPS parameter which the user must set to YES to obtain printed ply strength ratios is not required for the CSTRAT response type Only Item Codes 5 and 7 are available for this response Example TPL csrsens dat Listing 6 1 shows a complete input file that demonstrates the new feature Note the first DRESP1 with the CSTRAT response type has left the ATTB field blank so that the default first ply will be used for this response Listing 6 1 Input File with CSTRAT Response Type csrsens dat ID CSRSENS SOL 200 5 CEND TITLE TEST DRESP1 WITH RTYPE CSTRAT DSAPRT END SENS DESOBJ 3 DESSUB 100 DISP ALL FORCE ALL STRESS ALL ANALYSIS STATICS LOAD 10 BEGIN BULK CQUADA 101 101 1 2 3 4 DESVAR 1 ORIENT 20 790 90 0 ID LABEL RTYPE PTYPE REGION DRESP1 3 FISUM CSTRAT PCOMP 5 DRESP1 333 CFAILXX CSTRAT PCOMP 5 DCONSTR 100 333 1 0 1 01 0 1 101 2 101 116 DVPREL1 1 PCOMP 101 14 100 1 55190 FORCE 10 2 7 0 1 FORCE 0 3 70 1 GRID 1 0 0 123456 GRID 2 1 0 6 GRID 3 1 1 6 GRID 4 16 8 10 Ts 25 1 25 4 20 ds 100 100 T 20 6 PCOMP 101 1 410 HILL 0 1 2 220 YES 1 25 202 5 1 P2 15 ENDDATA The outputs of Figure 6 1 and Figure 6 2 were obtained from this example Note that the sensitivity indicates that the response in the second ply is a much weaker function of this des
9. Theory 128 a Input Output 128 Guidelines and Limitations 129 Benefits of Matrix Domain ACMS in SOL 200 130 m ADS Optimizer 131 Introduction 131 Benefits 131 Input 131 Remarks 133 Output 134 Guidelines and Limitations 134 Topology Optimization Beta Capability 135 Introduction 135 Benefits 136 Input 136 a TOPVAR Topological Design Variables 136 New Responses Compliance and Fractional Mass 137 New and Modified Design Optimization Parameters DOPTPRM 138 Outputs 139 Guidelines and Limitations 141 Example 1 topex1 dat 144 m BIGDOT Optimizer 147 Introduction 147 Benefits 147 Input 147 Output 148 Guidelines and Limitations 148 Example 148 7 Rotor Dynamics 8 DDAM Processor 9 Miscellaneous m Squeeze Film Damper Nonlinear Force 150 Introduction 150 a Squeeze Film Damper Model Imbedded in MSC Nastran Transient Solution 150 Theory for General Squeeze Film Damper Model 151 Squeeze Film Damper Input Data Format 152 Squeeze Film Damper Example 154 References 156 A DDAM Processor for MSC Nastran Including an MSC Patran Interface 158 Introduction 158 DDAM with SOL 187 158 m Guidelines for Effective DDAM Analysis 169 A Note on Symmetry 170 m Theoretical Background 172 Worked Two Mass Problem 178 Format of Coefficient File 185 Contro
10. Matrix of equivalent enforced motion load amplitudes due to stiffness effects Matrix of equivalent enforced motion load amplitudes due to viscous damping effects Matrix of equivalent enforced motion load amplitudes due to mass effects OEFNL1 MPT BGPDT ET CASECC OESNLH APPLOAD Table of element heat flow in SORTI format for nonlinear elements Output Data Block 1 TRD1 Format TRD1 Table of element heat flow in SORT1 format combined for linear and nonlinear elements CASECC TRL NLFT DIT PAR BXX MXX PXT SILD USETD VEC PXT0 UXT PNL YP NOUE NONCUP S NCOL FAC3 SETNAME NSOLT NOTRLDFM WTMASS SOL BGDD KCVDD R DG PXTDV CHAPTER 10 249 Upward Compatibility Input Data Block PXTDV TRLG Format TRLG Transient response load matrix in h set modal or d set combined from two executions of TRLG one with DVFLAG 0 and the other of DVFLAG 1 CAS ECC USETD DLT SLT BGPDT SIL CSTM TRL DIT GMD GOD PHDH EST MPT MGG VO1P RPX APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN S N S N l PET Hl PST fal EDT PDTI FO TOL DLTH YPT YPO TOLR PPT PXT NOSET S N PDEPDO IMETHOD STIME BETA 1 5 2 5 5 STIME S N NCOLT S N NSOLT DVFLAG 5 Input Data Blocks APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN
11. CHAPTER 6 143 Optimization To obtain a rib pattern by topology optimization a core non designable shell element thickness must be defined together with two designable above and below the core thicknesses That is add two designable elements for each regular element Elements referencing the composite property PCOMP entry cannot be designed Superelements are not supported Topology design variable cannot used together with other type design variables Topology design sensitivity is not supported Numerical problems often occur when solving a topology optimization task The nature of the problem depends on element type number of elements optimization algorithm and so on One frequent numerical problem is the so called checkerboard effect Checkerboard like material distribution pattern is observed in the topology optimization of continuum especially when first order finite elements such as CQUAD4 are employed to analyze structural responses It has been shown that the Checkerboard like phenomenon is caused by the finite element formulation The problem occurs because the checkerboard has an artificially high stiffness compared with a structure with uniform material distribution 1 The easiest way to decrease the checkerboarding effect is to use higher order elements such as COUADS This however increase the CPU time considerably Another closely related phenomenon is mesh dependent solutions It is seen that a more detailed stru
12. Method of centers Sequential quadratic programming Sequential convex programming ADS optimizer options Integer 1 5 Fletcher Reeves algorithm for unconstrained minimization d Davidon Fletcher Powell variable metric method for unconstrained minimization CHAPTER 6 Optimization 133 Table 6 3 DOPTPRM Design Optimization Parameters Name Description Type and Default Value 3 Broydon Fletcher Goldfarb Shanno BFGS variable metric method for unconstrained minimization 4 Method of feasible directions for constrained minimization 5 Modified method of feasible directions for constrained minimization K ADS one dimensional search options integer 1 8 1 Find the minimum of an unconstrained function using the Golden Section method 2 Find the minimum of an unconstrained function using the Golden Section method followed by polynomial interpolation 3 Find the minimum of an unconstrained function by first finding bounds and then using polynomial interpolation 4 Find the minimum of an unconstrained function by polynomial interpolation extrapolation without first finding bounds on the solution 5 Find the minimum of a constrained function using the Golden Section method 6 Find the minimum of a constrained function using the Golden Section method followed by polynomial interpolation 7 Find the minimum of a constrain
13. gt nd CHAPTER 2 71 Nonlinear Analysis 72 GRI GRI GRI GRI GRI CHEX1 CHEX1 7 8 COMMON DATA FOR EACH PROBLEM PSOLID8 1 MAT1 1 SFT MATS1 1 GRDSET ENDDATA EF tuu PRrRoONAA oO fs 10 10 10 10 0 PLASTIC C C0 rR 3 44 456 The results of element strain energy of the CHEXA element in the SUBCASE 100 are listed here INTOUT ALL NO MSC Nastran 2004 MSC Nastran 2005 8 583713E 04 2 175758 04 8 583713E 04 8 583713E 04 CHAPTER 3 Numeric Enhancements ACMS Now Available in the Matrix DOF Domain B Improvements for Geometric Domain Based ACMS B Improved Matrix Diagonal Diagnostics for 2x2 Pivots MAXRATIO Performance Improvement Modal Frequency Response for Large Frequency Ranges 3 1 ACMS Now Available in the Matrix DOF Domain Previously ACMS was available in the Geometric Domain The initial domain decomposition which divides the model into smaller sub models took place on the model geometry on the set of grid points and their element connections Now ACMS is also available in the DOF domain which postpones the domain decomposition until after all constraints have been eliminated at the matrix level DOF Domain ACMS is invoked with the Executive level command DOMAINSOLVER PARTOPT option DOMAINSOLVER ACMS PARTOPT DOF The primary advantage of DOF Domain ACMS is perf
14. 29 lt 29 200 22 8 29 260 229 29 ENDT 2 946 70 2 996 2 75 6 140 2 68 6 2 47 6 200 2 35 6 2 036 2505 195146 1 65 6 ENDT 1 4 6 TUS 1 4 6 1 29 6 140 1 24 6 1 15 6 200 2 196 810000 260 750000 500000 ENDT 80 150 220 280 80 150 220 280 80 150 220 280 80 150 220 280 80 150 220 280 80 150 220 280 79 1 4 6 24 6 78 6 55 6 12 5 C C CO 67 6 349 5 2218 5 415 5 erry 1546 07 6 05 6 06 6 529 529 29 29 94 6 64 6 2216 8 6 BS b 1 4 6 1 22 6 980000 620000 100 160 240 300 100 160 240 300 100 160 240 300 100 160 240 300 100 160 240 300 100 160 240 300 86 6 68 6 76 6 24 6 C C CO errr 46 5 52 26 07 6 04 6 08 6 o 529 29 29 529 2 82 6 2 58 6 2 09 6 1 65 6 1 34 6 1 2 6 870000 500000 168 5 328 54 299 5 tt tt CR CS GT CU CV CW CX CY CZ DA BX BY BZ CA CB CM CN A C4 E 5 GRID T GRID 2 GRID 4 GRID 5 SPCADD 2 1 5 1 123456 spcl T 123456 5 EMP 3 111 300 MPSET 111 4 5 EMP 3 101 310 TMPSET 101 1 2 5 TMPSE 710 11 AME 4 102 400 LD 102541 2 4 5 7 9 9 piz 5 201
15. 4 TEMP INIT should not reference and TMPSET CHAPTER 2 65 Nonlinear Analysis TMPSET Temperature Group Set Definition Define a time dependent dynamic thermal load group for use in TTEMP Bulk Data entry Format 1 2 3 4 5 6 7 8 9 10 TMPSET ID G1 G2 G3 G4 G5 G6 G7 Alternate Format TMPSET ID G1 THRU G2 BY INC Example The Continuation Entry formats may be used more than once and in any order They may also be used with either format above Continuation Entry Format 1 G8 G9 G10 G11 etc Continuation Entry Format 2 G8 THRU G9 BY INC Example TMPSET 15 5 THRU 21 BY 4 27 30 32 33 35 THRU 44 67 68 72 75 84 93 Field Contents ID Temperature group identification number Integer gt 0 Gi Grid point Identification numbers in the group Integer gt 0 66 Remarks 1 This entry is used in SOL 400 only when ANALYSIS NLTRAN nonlinear transient analysis and the temperature load is applied It only applies to the nonlinear elements in the Residual SEID 0 2 GROUP ID determines the group to a specified the time dependent distribution of temperatures It is used by TTEMP Bulk Data entry to define the corresponding TABLEDi entry GROUP ID must be unique for all the other TMPSET entries 3 TEMP INIT should not ref
16. PRINT ALL OLOAD PRINT ALL SUBCASE 1 LABEL GRAVITY LOAD VARIES IN THE X DIRECTION FOR A SQUARE PLATE LOAD 1 SUBCASE 2 LABEL GRAVITY LOAD VARIES IN THE Y DIRECTION FOR A SQUARE PLATE LOAD 2 BEGIN BULK CQUADR 1 1 2 7 6 CQUADR 2 2 3 8 7 CQUADR 3 3 4 9 8 CQUADR 4 4 5 10 9 CQUADR 5 6 7 12 11 CQUADR 6 7 8 13 12 CQUADR 7 8 9 14 13 CQUADR 8 L 9 10 15 14 CQUADR 9 11 12 17 16 CQUADR 10 L 12 13 18 17 CQUADR 11 L 13 14 19 18 CQUADR 12 L 14 15 20 19 CQUADR 13 16 17 22 21 CHAPTER 9 217 Miscellaneous CQUADR 14 1 17 18 23 22 CQUADR 15 1 18 19 24 23 CQUADR 16 1 19 20 25 24 5 4 6 qe Bc 9 0 ACCEL 1 267261 534522 801784 0 0 32 2 4 0 161 0 ACCEL 2 22 267261 534522 801784 Y 0 0 32 42 4 0 161 0 CORD2R 22 0 0 0 0 9 0 0 0 0 0 1 0 0 0 1 0 0 0 2 3 4 5 6 8 9 0 GRID BH 0 0 GRID 2 1 00000 GRID 3 2 000000 GRID 4 3 000000 GRID 5 4 000000 GRID 6 0 0 1 0 GRID 7 1 00000 1 0 GRID 8 2 0000001 0 GRID 9 3 0000001 0 GRID 0 4 0000001 0 GRID 1 0 0 2 0 GRID 2 1 00000 2 0 GRID 3 2 0000002 0 GRID 14 3 0000002 0 GRID 5 4 0000002 0 GRID 6 0 0 350 GRID 7 1 00000 3 0 GRID 8 2 0000003 0 GRID 9 3 0000003 0 GRID 20 4 0000003 0 GRID 21 0 0 4 0 GRID 22 1 00000 4 0 GRID 23 2 0000004 0 GRID 24 3 0000004 0 GRID 25 4 000000
17. Step 1 Calculate Natural Frequencies Equation of motion from free body diagrams ky x5 Ae S m P y kx mx yo 1 Summation of Forces 0 x4 ky k4 x4 k4X gt 0 IX kx x4 or in the more familiar matrix form 0 0 m Step 2 Solve the Equations k X2 k ky k ky CHAPTER 8 DDAM Processor N Il M This can be done manually or using a computer but the end result is the same Solution of these yields two modes with natural frequencies Q 8972 rad sec 0 196 6rad sec 14 280 Hz 31 285 Hz and corresponding eigenvectors MSC DDAM requires these to be mass normalized which can be accomplished by dividing each max normalized value by the generalized mass M d 0 mM Note that the generalized mass for a mass normalized vector set will be 1 for all modes The mass normalized eigenvectors will be x 0873 2329 2017 1008 Step 3 Calculate the Participation Factors They are determined from the following equations Note that the participation factors are normalization dependent Also note that MSC Nastran may have reversed the signs on the second eigenvector This simply changes some signs and the magnitudes of the participation factors in the intermediate steps The final solution is independent of the normali
18. The following dytran lsdyna files are potentially affected by the OUTR option OUTR OP2 XDB F06 PCH Not available in Version 2005 r1 Choose one or more or omit translate dytran lsdyna jid dytr d3plot output to MSC Nastran This option requires the use of the MSC Nastran Toolkit A license is not needed for the Toolkit as it is imbedded in standard SOL 700 licensing The conversion between LS Dyna s d3plot and op2 xdb f06 punch is made using MSC Patran s DRA DAC together with a special version of the toolkit The special toolkit executable is spawned from the original MSC Nastran job after dytran lsdyna completes and if any of the OUTR options are specified NP NP the number of processors domains for parallel processing The default is one In order to use more than one domain MPI Lam POE or whatever parallel program is needed must be properly installed on all computers involved and a hostfile CHAPTER 2 15 Nonlinear Analysis designating which computers are to be used for each domain must have been setup prior to running the job It is required that if NP gt 1 PATH 3 be used and a file named sol700 pth be located in the same directory as the MSC Nastran input data The sol700 pth file should contain all commands necessary to run dytran lsdyna in parallel This file must have execute permissions NOERROR NOERROR is an optional item If NOERROR is specified errors due to features that are available in MSC Nastran but not avai
19. c sol700 dytran lsdyna i enf2e dytr dat Ozenf2e dytr d3hsp G enf2e dytr d3plot D enf2e dytr d3dump F enf2e dytr d3thdt A enf2e dytr runrsf B enf2e dytr d3drfl 2 be used with Windows and Linux only If PATH 2 is specified it is expected that the directory with the dytran lsdyna run script is on the PATH If PATH 2 is specified dytran Isdyna will be executed from inside MSCNastran using the commands for the 1 option except that dynrun pth is not required PATH 3 Applicable to all computer systems If PATH 3 is specified a script or batch file to execute dytran Isdyna located in the same directory as the dytran lsdyna executable will be executed The name of the script or batch files is run dytran or run dytran bat This directory and name of the script is determined by the first line in a file named sol700 pth Options are specified on subsequent lines of the sol700 pth file CHAPTER 2 11 Nonlinear Analysis Available 3 options for Windows PC systems are as follows exe The full path to the executable for dytran lsdyna that is to be used Optional If exe is omitted the directory where the script or batch file resides first line of sol700 pth will be used and dytran lsdyna for UNIX Linux and dytran Isdyna exe for windows will be appended If exe is used it must be the second line in the sol700 pth file nproc Number of processors Default is to used NP on the SOL 700 line If NP an
20. can be used to specify the full path of its root name the logical key word for the root name is OPCASE The default root name is the MSC Nastran job name FORTRAN unit reference number 22 has been reserved by MSC Nastran for OPCASE Although the user can assign other FORTRAN unit numbers to it The full file name is in the form of root name gt lt suffix filename Also ppname and oplist are not required If ppname and oplist are specified they will be ignored Suffix filename must be specified with keyword TOCASE CHAPTER 9 231 Miscellaneous ASSIGN Assigns Physical File Assigns physical file names or other properties to DBset members or special FORTRAN files that are used by other FMS statements or DMAP modules Also assigns physical name and or other properties to Modal Neutral Files MNF for MSC Nastran ADAMS interface Format 1 Assign a DBset member name ASSIGN log name E TEMP DELETE SYS sys spec Format 2 Assign a FORTRAN file ASSIGN logical key f filename2 UNIT u STATUS NEW OLD UNKNOWN FORM FORMATTED 1 SIZE s UNFORMATTED BIGENDIAN LITTLEENDIAN LTLEND L lt ostype gt J DEFER TEMP DELETE SYS sys spec Examples 1 Assign the DBALL DBset ASSIGN DB1 filename of member DB1 INIT DBALL LOGI DB1 232 2 Assign FORTRAN file 12 to the OUTPUT4 module using the
21. file as shown in Table 6 2 Table 6 2 System Cell Summary System Cell System Function and Reference Number Name 413 OPTCOD Specifies which optimization code to be used in SOL 200 Optimization method is selected by parameter METHOD on DOPTPRM entry 0 default DOT Design Optimization Tool 1 Enhanced ADS code 132 The second way is that MSC Nastran allows users to select an ADS optimization algorithm is by a new parameter ADSCOD added to DOPTPRM Bulk Data entry that has the options shown in Table 6 3 Table 6 3 DOPTPRM Design Optimization Parameters Name Description Type and Default Value ADSCOD Optimization Code Integer gt 0 Default 0 see Remark 1 0 DOT used 1 ADS Modified Method of Feasible Directions 2 ADS Sequential Linear Programming 3 ADS Sequential Quadratic Programming 4 SUMT Method where I ADS strategy options Integer 0 9 Default 0 see Remark 2 0 None Go directly to the optimizer 1 Sequential unconstrained minimization using the exterior penalty function method 2 Sequential unconstrained minimization using the linear extended interior penalty function method 3 Sequential unconstrained minimization using the quadratic extended interior penalty function method 4 Sequential unconstrained minimization using the cubic extended interior penalty function method Augmented Lagrange multiplier method Sequential linear programming
22. 1 ELEMENTS CQUAD4 1 1 1 2 4 3 EG QE NO SUED 1 CQUAD4 4 1 7 8 14 13 CQUAD4 6 1 9 10 20 19 pe T PETIT MATI 1 290 T76 43 283 PARAM WTMASS 00259 PSHELL 1 1 05 1 1 ENDDATA 5 3 CHAPTER 5 105 Dynamic Analysis Automatic Q Set AUTOQSET Component modes or dynamic reduction are computed if the following items are defined in the input file 1 Mass is present 2 EIGR or EIGRL Bulk Data entry is requested by METHOD command or PARAM METHCMRS 3 Generalized coordinates q set degrees of freedom are defined The q set DOFs are defined on OSETi entries SEOSETi for superelements and associated SPOINT or GRID entries It is the user s responsibility to define a sufficient number of q set DOFs to capture all of the eigenvectors in the desired frequency range defined on the EIGR or EIGRL entry and residual vectors If too few q set DOFs are defined then modal truncation occurs and accuracy may suffer If too many then the dynamically reduced matrices will have null columns for the unused q set DOFs and may result in a performance degradation In MSC Nastran 2005 the user may replace all q set related Bulk Data entries with the user parameter PARAM AUTOOSET YES The number of component modes computed is determined by the frequency range and or number of desired engenvectors specified on the selected EIGR or EIGRL Bulk Data entry Since the generalized coordinates are automatically defined the f
23. 10 AUTO STEPNL 320 100 0 01 10 AUTO PLOAD4 510 101 D THRU 112 TLOAD1 100 510 0 0 120 TABLED1 120 TBD1 TBD1 0 0 5 l3 16 1 ENDT 1 100 Suc 0 3 283 2 1 101 3 7 0 3 283 2 51 100 PLASTIC 3 45 500000 5 GRID 10000 100 0 0 10 345 GRID 10001 100 0 0 0 0 345 GRID 10100 99 3625 3 30491 10 345 GRID 10101 99 3625 3 30491 0 0 345 GRID 10200 96 8149 6 51543 10 345 GRID 10201 96 8149 6 51543 0 0 345 GRID 10300 92 5105 9 59323 10 345 GRID 10301 92 5105 9 59322 0 0 345 GRID 10400 86 6025 12 5 10 345 GRID 10401 86 6025 12 5 0 0 345 GRID 10500 79 2443 15 1974 10 345 GRID 10501 79 2443 15 1974 0 0 345 GRID 10600 70 5889 17 6472 10 345 GRID 10601 70 5889 17 6472 0 0 345 GRID 10700 60 7898 19 8111 10 345 GRID 10701 60 7898 19 8111 0 0 345 GRID 10800 50 21 6506 10 345 GRID 10801 50 21 6506 0 0 345 GRID 10900 38 3729 23 1276 10 345 GRID 10901 38 3729 23 1276 0 0 345 GRID 11000 26 0617 24 2037 10 345 GRID 11001 26 0617 24 2037 0 0 345 GRID 11100 13 2197 24 8406 10 345 GRID 11101 13 2197 24 8406 0 0 345 GRID 11200 0 0 25 10 345 GRID 11201 0 0 20 0 0 345 CQUAD4 101 100 10000 10001 10101 10100 CQUAD4 102 100 10100 10101 10201 10200 CQUAD4 103 100 10200 10201 10301 10300 CQUAD4 104 100 10300 10301 10401 10400 CQUAD4 105 100 10400 10401 10501 10500 CQUAD4 106 100 10500 10501 10601 10600 CQUAD4 107 100 10600 10601 10701 10700 CQUAD4 108 100 10700 10701 10801 10800 CQUAD4 109 100 10800 10801 10901 10900 C
24. 102 V S V 0 0 1 5 100 4 5 370 ENDT FORCE 100 12 100 NS FORCE 200 12 150 d FORCE 300 12 195 13 FORC FORC FORC FORC LPA DU DE do rd Ze S m B 0 ENDDATA 400 12 500 12 600 12 700 12 400 1 Te96 25 12 250 2 995 330 370 Pepe ITER CHAPTER 2 69 Nonlinear Analysis B The displacement results at the tip of the ROD element are listed here STEP Theoretical 1 000000E 04 MSC Nastran 2004 1 000000E 04 1 000000E 04 E MSC Nastran 2005 1 526316E 04 1 526316E 04 1 526316E 04 2 000000E 04 2 000000E 04 2 000000E 04 2 611111E 04 2 611111E 04 2 611111E 04 3 000000E 04 3 000000E 04 3 000000E 04 3 529412E 04 3 635294E 04 3 529412E 04 4 000000E 04 4 105882E 04 4 000000E 04 3 000000E 05 4 058823E 05 2 999997E 05 Note that in the loading procedure from STEP1 to STEP 7 MSC Nastran 2004 built numerical error gradually but not in MSC Nastran 2005 when comparing with the theoretical results The last STEP STEP 100 is an unloading procedure MSC Nastran 2005 can obtain the very close result as the theoretical one but MSC Nastran 2004 has about 35 error in the residual displacement 2 5 Correction for the Nonlinear Element Strain Energy By using the Case Control command ESE the user can ask NASTRAN job to compute and output the element strain energy in all linear analyses for a
25. 23 outputs 52 CDAMPID 17 23 PARAM NLPACK 52 PARAM PH2OUT 52 STEP 43 TLOADI 51 TMPSET 44 51 TSTEP 43 TSTEPNL 44 TTEMP 44 51 SOL 600 beam 33 Bulk Data Entries PARAMARC 40 Bulk Data Parameters MARCFIL1 35 MARCOUTR 40 MARCWIND 41 MRAFFLOW 39 MRMTXNAM 35 MRRCFILE 36 MRSPAWN2 36 CONTINUE 33 dmap 33 Implicit Nonlinear 33 CDAMP2D 17 23 CELASID 17 23 CELAS2D 17 23 CFILLET 18 23 COMBWLD 19 23 CSPOT 18 23 DAMPGBL 19 23 EOSPOL 19 23 MATD001 23 MATD003 24 MATD005 24 MATD006 24 MATD012 24 MATD013 24 MATD014 24 MATD015 24 MATD018 24 MATD019 24 MATD020 24 MATD022 24 MATDO024 24 MATD026 24 MATD027 24 MATD028 24 MATD031 24 MATD054 24 MATD057 24 MATD059 24 MATD062 24 MATD063 24 MATD064 24 MATDO077 25 MATD080 25 MATD081 25 MATD100 25 MATD127 25 MATD181 25 MATD20M 20 24 MATD2AN 24 MATD2OR 23 MATDxxx 20 MTD030 24 RBE3D 22 25 23 TICD 23 25 WALL 23 25 Bulk Data Parameters DYBEAMIP 26 DYBLDTIM 25 DYBULKL 25 DYCMPFLG 26 DYCONECDT 25 DYCONENMASS 25 DYCONIGNORE 25 DYCONPENOPT 25 DYCONRWPNAL 25 DYCONSKIPRWG 26 DYCONSLSFAC 25 DYCONTHKCHG 25 DYCOWPRD 25 DYCOWPRP 25 DYDCOMP 27 DYENDTIM 25 DYENERGYHGEN 26 DYENGFLG 26 DYEPSFLG 26 DYHRGIHQ 26 DYHRGQH 26 DYIEVERP 26 DYINISTEP 25 DYLDKND 25 DYMATSI 25 DYMAXINT 26 DYMAXSTEP 26 DYMINSTEP 26 DYN3THDT 27 DYNAMES 25 DYNEI
26. 409337 03 4 590343 03 2 426860 01 Since the DMIG matrix names are defined by character names rather than by enumerated values such as element identification they currently cannot be individually selected by SET selection of the ESE Case Control command The parameter DMIGNRG is used to include the DMIG matrix energy to the Total Energy calculation and provide individual matrix contribution information The default of DMIGNRG is NO To include the DMIG contribution the Bulk Data parameter DMIGNRG should be set to YES Example files ab1 2 3 4 dat can be found in the TPL 4 4 Bar Element Torsional Mass Moment of Inertia In prior versions of MSC Nastran the BAR element did not include the torsional mass moment of inertia in the mass matrix This led to different results when compared to the BEAM element for an equivalent structure This limitation is documented as CSR7832 The torsional mass moment of inertia can now be included in the BAR mass matrix by using NASTRAN SYSTEM 398 1 or NASTRAN BARMASS 1 Note that by default this term will not be included For both values of PARAM COUPMASS this term is added If desired the system cell default value can be changed via the NASTRAN rc file The BAR torsional mass moment of inertia term for the component of rotation about the element axis is calculated similar to the BEAM element using the following equation Lx PLU D where I Torsional Mass Moment o
27. 53933E 01 12 53 1 80594E 03 1 44653E 02 8 30642E 02 100 8 2 83923E 03 5 37783E 02 6 37984E 02 9 22442E 08 1 90999 08 14 50 3 00425E 03 3 72761E 02 1 31574E 03 200 1 2 81691E 02 2 90048E 02 3 28924E 02 3 49256E 00 3 51245E 01 24 50 4 31611E 02 4 39967E 02 4 35789E 02 200 3 2 73870E 03 1 10669E 01 1 04747E 02 9 62188E 00 4 12887 01 87 82 1 50513E 01 2 74268E 03 1 37887E 03 200 4 1 27601E 02 8 43308E 01 4 03806E 01 9 82619E 00 6 18361E 01 10 43 1 35034 02 9 17641 01 1 13399 02 200 5 7 30090E 02 7 11099E 01 2 39860E 01 9 62188E 00 4 12887E 01 88 29 7 18274E 01 7 30808E 02 4 01318E 02 200 6 2 79715E 03 6 88072E 01 8 83526E 01 3 49256E 00 3 51245E 01 1 76 2 79987E 03 7 15284E 01 1 43570 03 200 8 3 93539E 02 2 43778E 02 3 62750 02 3 93396 16 3 95636E 17 65 65 4 07956E 02 5 57717 02 4 82836E 02 300 1 4 06549 02 1 07470E 02 1 66640 02 4 97689E 00 5 17350E 02 65 95 3 31102 01 4 80909 02 2 23900 02 300 2 3 15888E 02 3 21002E 01 9 81308E 01 7 62246E 00 8 59908E 02 72 67 1 47298 00 3 46515E 02 1 72521 02 300 3 1 47324E 02 3 80228E 01 1 87526E 01 8 54160E 00 9 08978E 02 84 28 3 99010E 01 1 49203E 02 9 45518E 01 300 4 1 74069E 02 9 78514E 01 4 22159E 01 7 95162E 00 8 88424E 02 23 96 1 92833E 02 7 90880E 01 5 68725E 01 300 5 8 33154E 01 1 96665E 02 6 56791E 01 6 67973E 00 3 56612E 02 77 43 2 11307 02 9 79570 01 1 54632E 02 300 8 5 06968E 02 2 38382E 02 1 75908E 02 9 22442 08 2 1768
28. 8 PARAM GRDPNT 0 HL d Datos ats diea me s AB sss DON iss deg 78 TSTEP 98g 30001 000010 100 5 DLOAD 200 1 0 20 0 301 20 0 302 TLOAD2 301 301 LOAD 0 0 TLOAD2 302 302 LOAD 0 0 F f UNBAL f 2 1 453 5924 lbm gm UNBAL f 2 2 25243e 4 lbf where UNBAL is given in GM IN freq in Hertz 5 1 0 10000 2 p1 60 2 453 6 386 4 5 6 2619 for 10 000 RPM DAREA 301 101 1 6 256715 DAREA 302 101 2 5 256718 5 Structural Model CONM2 99 101 0 100 GRID 101 0 0 0 0 0 0 0 0 GRID 102 0 0 0 0 0 2 0 0 5 5 CENTERING SPRINGS FOR SQUEEZE FILM DAMPER CELAS2 101 100000 101 dh 102 1 CELAS2 102 100000 101 2 102 2 Spring to ground GRID 103 0 0 0 0 0 0 0 0 CELAS2 111 1 49 103 1 102 1 CELAS2 112 FQ 103 2 102 2 SQUEEZE FILM DAMPER INPUT Siu auus d E DL S s iS Anu scis 56558615 oes tous d 78 NLRSFD 1 101 102 XY 6 44 2 7 t MA 0 0 1 0 0 180 0 31 155 156 5 ENDDATA Figure 7 3 SFD Force X and Y Direction References 1 Adams M L Padovan J Fertis D G Engine Dynamic Analysis With General Nonlinear Finite Element Codes Part 1 Overall Approach and Development of Bearing Damper Element ASME Journal of Engineering for Power Vol 104 July 1982 pp 586 593 Castelli
29. ASCII option ASSIGN OUTPUT4 filename of FORTRAN file UNIT 12 FORM FORMATTED 3 Assign FORTRAN file to the OPCASE using the ASCII option ASSIGN OPCASE Filename of FORTRAN file STATUS NEW 4 Define SYS parameters for the SCR300 DBset file using the default file name ASSIGN SCR300 SYS 5 Setthe default OP2 file format to BIGENDIAN and assign two OP2 files one to unit 12 with the file name test op2 12 and one to unit 35 with file name test_op2 35 in ASCII mode ASSIGN OP2 BIGENDIAN ASSIGN OP2 2 test op2 12 UNIT 12 ASSIGN OP2 test op2 35 UNIT 35 FORM FORMATTED Describer Meaning log name The name of a DBset member name log name may also be referenced on an INIT statement after the LOGICAL keyword filename1 The physical filename assigned to the DBset member If the default logical key filename2 UNIT u TEMP DELETE filename if there is one is to be used filenamel may be omitted or specified as or See Remark 6 Specifies defaults for STATUS UNIT and FORM of FORTRAN files for other FMS statements DMAP modules punching and plotting operations The physical file name assigned to the FORTRAN file If the default filename is to be used filename2 may be omitted or specified as or See Remark 7 uis the FORTRAN unit number of the FORTRAN file If this describer is omitted and if filename2 is omitted this ASSIGN statement will
30. Coefficients from File or form compiled source T coefficients from external file 188 F use built in coefficients Ignored if first item is T Third item Equation format T DDS 072 style equations F NRL 1396 style equations Ignored if first item is T Second Line file name if needed format a80 If 1 item on line 1 is T Name of spectrum file e If 2 4 item on line 1 is T Name of coefficient file f neither are T line is not needed Third Line location flags format i1 1x i1 1x i1 First item Surface or Submarine 1 Surface 2 Submarine Second item equipment location 1 Deck 2 Hull 3 Shell Third item coefficient class 1 Elastic 2 Elastic Plastic e 4 ine Weight cutoff percentage format F8 3 Cutoff percentage 0 To 100 e 5t Line Minimum G cutoff format F8 3 Minimum G level to use in Gs 6th Line Axis Orientation format 1 1 1 First item F A axis CHAPTER 8 189 DDAM Processor X Y or Z Second item Vertical Axis X Y or Z 7th Line Input file format a80 Name of file full path if needed 8 Line Output file format a80 Name of file full path if needed e 9th Line verification file format a80 Name of file full path if needed Thesenames will be ignored if they are passed as arguments when the DDAM program is run Note that the spacing of the first line and the axis defin
31. Hour GDACMS MDACMS S MDACMS P One Design Cycle gi One FE Analysis 6 7 CHAPTER 6 131 Optimization ADS Optimizer Introduction ADS is a public domain FORTRAN program for Automated Design Synthesis developed by G N Vanderplaats in 1985 and is documented in Vanderplaats G N ADS FORTRAN Program for Automated Design Synthesis Version 1 10 NASA Contractor Report 177985 NASA Langley Research Center Hampton Virginia 1985 In MSC Nastran 2005 an MSC Software enhanced ADS version is added to support SOL 200 Benefits The availability of the ADS optimizer provides an alternative to the existing optimizer options that are provided in the DOT optimizer that has been the workhorse optimization algorithm for many years As indicated below the ADS code is a suite of optimization techniques and it may be that a particular optimization task will achieve improved results when using one of the ADS techniques Notably ADS contains SUMT Sequential Unconstrained Minimization Techniques methods that are not available with DOT Users who have had experience in the use of the public domain ADS code should welcome having these algorithms available in MSC Nastran The ADS optimizer will use your current optimization license and does not require any special licensing Input There are two ways to use ADS code One way is by modifying an executive system parameter OPTCOD in the Runtime Configuration RC
32. Matrix Multiplication E Acceleration Loads ACCEL and ACCEL1 Bulk Data Entries B A Caution Concerning MSC Access Application Development B Divergent Thermal Results Error Correction Q1 0768221 B Displacement Output Filters E Write Results Recovery for Subcases into Separate F06 Files bil 9 1 MSC Nastran ADAMS Integration Overview An additional capability has been added to allow the user to create a MSC ADAMS modal neutral file MNF that does not contain any modal data The purpose for this would be to aid model checkout and to determine the location of attachment points A RIGID option has been added to the mass invariant MINIVAR describer on the ADAMSMNE Case Control command ADAMSMNF FLEXBODY YES MINVAR RIGID Also PARAM AUTOOSET YES can be used with this option that allows the required SPOINTs and QSETs to be supplied by the program automatically This parameter should specified in the Case Control Section above Subcase level Limitations This option will work for a residual structure only model If PARAM AUTOOSET YES is specified to automatically generate SPOINT and QSET entries then there should be no SPOINTs or 5 present in the bulk data In order to determine the location of attachment points there should be no SPOINTs or OSETs present in the bulk data and PARAM AUTOOSET YES should not be present in the Case Control Section 9 2 CHAPTER 9 Miscellaneous 199 Alternative Solution Algori
33. Optimization Parameters Description Default Value TCHECK Topology Filtering options integer 0 or 1 1 Filtering algorithm is on for topology optimization default 0 No filtering algorithm Topology minimum member diameter real gt 0 0 in the basic coordinate system Default 0 0 i e no minimum member size control This option is applied on 2 and 3 D elements only CHAPTER 6 Optimization Table 6 6 Default Values for DOPTPRM Design Optimization Parameters Parameter Sizing Shape Topology DESMAX 5 30 1 0 001 1 0 5 CONVDV 0 001 1 0E 4 DELX 0 5 0 2 DXMIN 0 05 1 0E 5 As a final comment on DOPTPRM parameters it was necessary to change the definition of the P2 parameter that controls the amount of print that occurs at design cycles specified by P1 For sizing and shape optimization design variables are printed for any value of P1 1 orif 1is including in the sum of the options Since a topology optimization task can easily result in thousands of design variables this would not be a viable option for most problems Instead design variable prints are turned off unless P2 value greater than 8 is specified Outputs P2 1 default on Bulk Data entry DOPTPRM does not print topology design variables to minimize optimization output since topology optimization involves in a large number of design variables P258 prints topology design variables Output in for the two new
34. POINT COLUMN 1 11 719 1 11095 01 11 R3 1 11095 00 COLUMN 2 TITEL T2 11095 01 COLUMN 3 11 T3 T3 11095 01 11 R1 1 11095 00 COLUMN 4 11 R1 T3 11095 00 11 R1 1 11095 01 COLUMNS 5 4 11 R2 THRU 11 R2 ARE NULL COLUMN 6 11 R3 11095 00 11 R3 1 11095E 01 COLUMN 7 11095 01 12 R3 1 11095 00 COLUMN 8 Aa Te y 11095 01 COLUMN 9 t 22 13 1 11095 01 12 R1 1 11095E 00 COLUMN 10 12 R1 1 11095 00 12 R1 1 11095 01 With System Cell 414 set to 1 the mass matrix contains only diagonal terms 0 MJJX POINT VALUE POINT VALUE POINT VALUE POINT COLUMN derit 11 11 11 T1 1 11095E 01 COLUMN 2 11 T2 11 T2 1 11095 01 COLUMN 32 11 3 11 T3 1 11095 01 COLUMNS 11 R1 THRU 6 11 R3 ARE NULL COLUMN 7 12 71 12 T1 1 11095E 01 COLUMN 8 12 12 12 T2 1 11095E 01 COLUMN 9 12 13 12 T3 1 11095 01 COLUMNS 10 12 R1 THRU 12 12 R3 ARE NULL 4 6 QUADR Convergence Behavior Introduction A new QUADR element has been introduced in MSC Nastran 2005 to provide more accurate results for coarsely meshed regions where accuracy would tend to degrade In recent tests the new QUADR element was compared to the QUAD4 element The results of the testing showed that the new QUADR element produced more accurate results even in regions that were coarsely meshed Benefits Overall an increase in accuracy can be expected when using th
35. Parameter DVFLAG Matrix of applied load amplitudes Matrix of equivalent enforced motion load amplitudes due to stiffness effects Matrix of equivalent enforced motion load amplitudes due to viscous damping effects Matrix of equivalent enforced motion load amplitudes due to mass effects Matrix of enforced motion amplitudes Input integer default 0 Enforced motion processing flag for both the large mass and direct methods of specification 250 0 Process only applied loads and excitations due to enforced accelerations default gt 0 Process only excitations due to enforced displacements and velocities WEIGHT The SEID parameter has been moved to the 4th position Format WEIGHT VELEM EST MPT DIT OPTPRM OGPWG DESTAB XINIT WMID WGTM WGTVOL S N VOLS S N FRMS SEID DOFRMASS Input Data Blocks DESTAB Table of design variable attributes XINIT Matrix of initial values of the design variables Parameters FRMASS Output real default 0 0 Fractional mass of designed structure SEID Input integer default 0 Superelement identification number DOFRMASS Input integer default 0 Fractional mass flag 10 2 CHAPTER 10 251 Upward Compatibility Summary of Data Block Changes from MSC Nastran 2004 to MSC Nastran 2005 The following material describes changes in table data blocks for only those records that existed in MSC Nastran 2005 DYNAMIC Table of Bulk Data entry images related t
36. Processor Elastic Plastic can be ELASTIC or PLASTIC reflecting the use of the elastic design coefficients or the elastic plastic design coefficients Weight Cutoff controls how many modes are used for the NRL sum All modes up to the specified modal mass percentage specified will be included in the NRL sum for each direction The DEFAULT switch will use the percentage that is hard coded into the program If the ENTER VALUE switch is chosen the cutoff should be entered as a percentage not a decimal e g 90 instead of 90 Minimum G Level controls whether the calculated spectra values should be replaced with a minimum if they fall below a certain threshold The N A switch will use the value that is calculated regardless of its magnitude If the ENTER VALUE switch is chosen the minimum cutoff should be entered as a value e g 1 0 instead of 386 4 The two axis toggles tell DDAM which direction of the model is oriented in the fore aftand vertical directions Each button has possible choices of X Y and Z An error will be issued if both axes are set to be the same 196 CHAPTER 9 Miscellaneous E MSC Nastran ADAMS Integration B Alternative Solution Algorithms for Flutter Analysis E Little Big Endian Reduced OP2 File SET Consistency Check SPC and SPCD Entries in Machine Precision Reading of PUNCHed Long Field Format Bulk Data B New Complex Conjugate Option for
37. TRIAR CHAPTER 4 81 Elements COMPMATT Enable Yes Smear Supported Supported update of Nonsmear Not Supported Supported temperature dependent composite properties No default Supported Supported EPSILONT Select Secant default Supported Supported Integral or Secant thermal strain Integral Supported Supported calculation method Example ASSIGN PUNCH OUTDIR shcntr2p n NEW UNIT 7 id msc shcntrl2 dat v2005 9 Jun 2004 hdp SOL 106 TIME 600 Direct Text Input for Executive Control CEND SEALL ALL SUPER ALL TITLE shape control demo n2 ECHO NONE MAXLINES 999999999 Direct Text Input for Global Case Control Data TEMPERATURE INITIAL 1 SUBCASE 1 Subcase name Default SUBTITLE Default NLPARM 1 SPC 2 TEMPERATURE LOAD 3 DISPLACEMENT SORT1 REAL plot ALL Direct Text Input for this Subcase OUTPUT XYOUT XYPUNCH DISP 333 T3 370 T3 BEGIN BULK PARA POST 1 PARA COUPMASS 1 PARA LGDISP 1 PARA K6ROT 100 PARAM NOCOMPS 1 PARA PRTMAXIM YES PARAM COMPMATT YES PARA NLTOL 0 LPARM 1 10 ITER 100 YES Direct Text Input for Bulk Data Elements and Element Properties for region smahcelem Composite Property Record created from P3 PATRAN composite material record smahclam Composite Material Description PCOMP 1 70 0 004
38. V and Shapiro W Improved Method for Numerical Solutions of the General Incompressible Fluid Film Lubrication Problem ASME Journal of Lubrication Technology Vol 89 No 2 1967 pp 211 218 Adams M L Padovan J Fertis D G Finite Elements for Rotor Stator Interactive Forces in General Dynamic Simulation Part 1 Development of Bearing Damper Element NASA CR 165214 EDA 201 3A October 1980 Ghaby R Transient Nonlinear Vibration of Gas Turbine Engines With Squeeze Film Dampers Due to Blade Loss May 1984 Master of Science Thesis Case Western Reserve University Black G Gallardo V Blade Loss Transient Dynamics Analysis Task II TETRA 2 User s Manual NASA CR 179633 November 1986 CHAPTER DDAM Processor E A DDAM Processor for MSC Nastran Including an MSC Patran Interface E Guidelines for Effective Analysis E Theoretical Background Worked Two Mass Problem E Format of Coefficient File E Control File Format User defined Shock Spectra MSC Patran Interface 8 1 Processor for MSC Nastran Including an MSC Patran Interface Introduction This chapter describes a method for the calculation of the response of a structure using the Dynamic Design Analysis Method DDAM in MSC Nastran The Theory Section has been implemented in MSC Nastran and in a FORTRAN code Due to the classified nature of specific DDAM shock environment calculations it may be n
39. When the object exists it is checked for a conflict to another logical file When no conflict exists then a check for available processing space i e less than thirty logical files currently open is made When space is available the DAT control area is copied to the available control area The remaining control fields are initialized for object management 221 222 The logical handle number and words per record are returned to the calling application program Subroutine Name OPENSQ 1 Entry Point OPENSQ 2 Purpose Open a keyed object for sequential processing and return logical file reference 3 Calling Sequence CALL OPENSQ DBNUM NAME FILNUM KEYLEN IRET DBNUM Integer input Logical database number NAME Array input Object dictionary entry and object to open Integer output Logical handle number assigned to object KEYLEN Integer output The number of words in the key 0 gt Used Hierarchal Method n gt Used B Tree Method IRET Integer output Return code from the routine 0 gt Normal data block open 1 Requested object does not exist 2 Too many logical files open 3 gt Unused 4 gt Object already open for update 4 Method This routine can only be used to open keyed objects for read access The existence of the object is determined by DICRDR and its form keyed is verified Control areas are created for logica
40. X X X X X X X X dA da da dn da dn dao dao X X X HY ur 5 SOL 101 5 STATIC ANALYSIS CEND 5 DISPL 200 FORCE 100 LOAD 85 MPC 1 set 100 27 35 25 41234 123 thru 134 9701 9901 set 200 1 thru 5 1005 BEGIN BULK param 1 5 5 tested feature controls 5 param oelmset 100 5 select reduced element SET ID from case control param ogrdset 200 5 select reduced point SET ID from case control param opchset 1 punch element related point set in SET format param omsglvl 1 5 WARNING message only 5 Spoint 20001 21001 Spoint 30001 celas3 9701 175 20001 celas3 9702 175 21001 celas3 9801 175 30001 celas3 9901 175 40001 5 GRID 777 10 0 CHAPTER 9 Miscellaneous ENDDATA Example Output The example problem contains inconsistent sets The MSC Nastran run terminates with FATAL messages identifying the inconsistencies as shown in the following excerpt from the f06 listing USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 21 NOT PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 22 NOT PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SU
41. all coefficients in an external file the notation user coefficients will appear after the configuration for which coefficients were entered The specific equations implemented in this program are documented in Format of Coefficient File on page 185 ENTER F A DIRECTION XX ENTER VERTICAL DIRECTION X Y or 2 CHAPTER 8 165 DDAM Processor These two questions establish the coordinate directions for the application of the directional shock scaling factors These are the AF and VF in the spectrum equations This specification allows models built in non standard MIL spec coordinate directions X forward Y athwartship Z up to be processed by DDAM with the loads applied in the correct directions Is this a multiple or single mode analysis CR normal s single mode This option is provided if the user wishes to examine the contribution of a single mode to the overall summed response Choosing the s option will generate a prompt asking for the mode number of interest The program then generates a f13 file containing factors of zero the UHVi for all modes except the one chosen This will result in displacements stresses etc for the model as if the entire response consisted of just a single mode Note that this single mode will be NRL summed so the signs will lost For normal DDAM analysis choose the normal option The PARTNVEC matrix and the BY
42. and can be designated to specific files using an ASSIGN statement ASSIGN OUTPUT2 job_mbm_x op2 UNIT 41 DELETE CHAPTER 8 167 DDAM Processor Output is controlled by requests in the case control file so if you have requested STRESS ALL and then request mode by mode data you will get mode by mode stresses for all modes Again if this is necessary be wary of the volume of data that can be easily produced Output in the f06 file is labeled with section headers Each mode by mode section is preceded by a small header Important Note Displacements accelerations and velocities are all labeled as Eigenvectors look at the magnitudes to make sure you have the right one Special Circumstances Single shock direction calculations If you only need output for a single shock direction you can use PARAM entries to skip particular directions PARAM XSHOCK PARAM YSHOCK NO PARAM ZSHOCK YES If using DTI input to pick certain modes you still have to define the 3 column matrix this is just to cut down on post processing output This capability is especially useful to cut down output when using the mode by mode capability Special Circumstances Running the Fortran part of the Analysis Separately There are circumstances where it may be necessary to run the Fortran program separately from the MSC Nastran job Since the program runs automatically by default it is necessary to add some parameters to disable the automatic
43. and the residual vectors are now computed REAL MODE NO YOUR EIGENVALUES EXTRACTION ORDER 20 050 NP EIGENVALUE BNP oa Hn 881936 04 011058 05 524259 06 816616 06 175494 07 435711 07 506449 07 BEFORE AUGMENTATION OF RESIDUAL VECTORS RADIANS CYCLES 1 371837 02 2 183346E 01 5 487311E 02 8 733327E 01 1 234609E 03 1 964941E 02 2 194679E 03 3 492940E 02 3 428547E 03 5 456702 02 4 935292 03 7 854762 02 6 713009 03 1 068409 03 GENERALIZED MASS 000000 00 000000 00 000000 00 000000 00 000000 00 000000 00 000000 00 BNP aS p GENERALIZED STIFFNESS 881936 04 011058 05 524259 06 816616 06 175494 07 435711 07 506449 07 107 108 REAL MODE NO 0 EIGENVALUES EXTRACTION ORDER EIGENVALUE AR 881936 04 011059 05 524259 06 816615 06 175493 07 435711 07 506449 07 003539 07 442988 08 AFTER UF AUGMENTATION OF RESIDUAL VECTORS RADIANS CYCLES 371837 02 2 183346 01 487311 02 8 733327 01 234609 03 1 964941 02 194679 03 3 492940 02 428547 03 5 456702 02 935292 03 7 854761 02 713009 03 1 068409 03 488698 03 1 510173 03 201244 04 1 911840 03 PRPPP PPR BR GENERALIZED MASS 0000
44. aware of this extra final design variable the transformed objective and constraint values and the effects this has on the sensitivities Guidelines and Limitations The method does not apply when the design task given the optimizer is feasible Setting PENAL 2 0 seems to work well but users are free to experiment with their application PENAL must be a positive real number 0 0 is valid but has no effect Example TPL mmfdpen dat TPL file mmfdpen shows the use of the PENAL parameter in conjunction with the DOT algorithm for the Modified Method of Feasible Directions The file is the existing mmfd dat TPL file with the DOPTPRM entry modified to 1 2 3 4 5 6 7 8 9 10 DOFIFRM P1 1 p2 15 DELP 0 5 DESMAX 30 PENAL 10 124 Even though the DOT algorithm that is used for mmfdpen and mmfd contains strategies to deal with initially infeasible designs the use of the PENAL parameter showed a reduction in the number of design cycles and a slight insignificant improvement in the final design as shown in Table 6 1 Table 6 1 Number of Design File Name Final Objective 6 4 CHAPTER 6 125 Optimization Residual Vectors Based on Adjoint Loads Introduction A new RESVEC option has been introduced that creates residual vectors for use in a modal frequency response analysis that are based on adjoint load vectors which are in turn are created from user input DRES
45. contents of the grid point list connected to the elements in the OELMSET Case Control SET There is no consistency check for OGRDOPT 2 or OGRDOPT 3 OGRDOPT 0 turns the SET consistency check off altogether For this case the grid points retained are those specified in the OGRDSET SET and the elements retained are those specified in the OELMSET SET Outputs The SET consistency check feature of the reduced op file size capability produces printed output other than standard format MSC Nastran FATAL and or WARNING messages Punched output can be produced at the user request The punched output consists of a Case Control SET of the grid point IDs that are consistent with the OELMSET Case Control SET of elements Guidelines and Limitations Large THRU ranges in the grid point Case Control SET definition can generate large amounts of informational messages if the grid points in the THRU range are not present in the model CHAPTER 9 Miscellaneous SPOINT IDs are treated as GRID point IDs The SPOINT data record on the element connection data block GEOM2 is not modified if it exists Rigid element connections are ignored Only finite element connectivity is examined for attached grid points If duplicate element IDs across element types are encountered no warning message is generated All elements with same ID will be processed if the ID is in the OELMSET Case Control SET This feature is active only when op2 postprocessing file
46. dynamic excitations The enhancements mentioned above not only result in increased accuracy for dynamic response calculations on double precision machines but also facilitate more efficient processing of these excitations in subsequent modules S 5 5 Enhancements to Transient Response Analysis Increased Accuracy from TRLG Module The TRLG module generates time dependent dynamic excitations applied loads and enforced motion data for subsequent use in transient response calculations Prior to MSC Nastran 2005 these excitations were generated in single precision Starting with MSC Nastran 2005 these excitations are generated in machine precision thereby resulting in increased accuracy for transient response calculations on double precision machines Improved Calculations for Enforced Motion in TRLG and TRD1 Modules The differentiation scheme employed in the TRLG module for enforced displacement and enforced velocity applications in transient analysis has been improved in MSC Nastran 2005 by employing the same central finite difference scheme that is used in the subsequent TRD1 module which performs the solution phase for linear transient analysis see Chapter 6 of the MSC Nastran Basic Dynamic Analysis User s Guide Appropriate enhancements have also been made to the TRD1 module to account for these TRLG changes These improvements impact enforced motion usage in transient analysis not only for the SPC SPCD approach but also the la
47. entered That form looks like 194 The Spectrum Source option menu has two choices COEFs and Spectrum Source C FILE Cosi Source DEFAULT e COEFs will instruct X m ae DDAM to obtain the shock Coefficient Options spectrum and spectral HAE T accelerations from a set of Location neck coefficients Elastic Plastic FILE allows input of a general spectrum not determined by coefficients If FILE is chosen the file can be chosen using the Spec Source button that will appear The Coef Source option menu dictates where the coefficients are to be found e DEFAULT will use the coeffiecients that are hard coded into the DDAM program FILE will pull them from a file previously created by the user who must then pick the file using the Coef File button that will appear If the Spectrum Source is FILE then the Coefficient Options items are enabled Each menu has several choices that will allow the user to choose which set of coefficients is desired If the coefficients are coming from a file and the file does not contain coefficients for the particular configuration that has been specified the default coefficients will be used At the moment no warning of this is given Ship Type can be SURFACE or SUBMERGED Mount Location can be DECK HULL or SHELL CHAPTER 8 195 DDAM
48. for Windows Support vn4w support mscsoftware com MSC visualNastran Desktop 2D Support vn2d support mscsoftware com MSC visualNastran Desktop 4D Support vndesktop support mscsoftware com MSC Dytran Support mscdytran support mscsoftware com MSC Fatigue Support mscfatigue support mscsoftware com Interactive Physics Support ip support mscsoftware com MSC Marc Support mscmarc support mscsoftware com MSC Mvision Support mscmvision support mscsoftware com MSC SuperForge Support mscsuperforge support mscsoftware com MSC Institute Course Information msctraining support mscsoftware com Training The MSC Institute of Technology is the world s largest global supplier of CAD CAM CAE PDM training products and services for the product design analysis and manufacturing market We offer over 100 courses through a global network of education centers The Institute is uniquely positioned to optimize your investment in design and simulation software tools Our industry experienced expert staff is available to customize our course offerings to meet your unique training requirements For the most effective training The Institute also offers many of our courses at our customer s facilities The MSC Institute of Technology is located at 2 MacArthur Place Santa Ana CA 92707 Phone 800 732 7211 Fax 714 784 4028 The Institute maintains state of the art classroom facilities and individual computer graphics laboratories at training centers through
49. generation is requested for the MSC Patran program v3 or higher param post 1 with geometry output Case control grid point related output requests e g DISP must reference the OGRDSET Case Control SET Case control element stress strain and force requests e g STRESS must reference the OELMSET Case Control SET Not available when superelements are present Demonstration Example A simple example is presented that demonstrates the set consistency check feature The model is composed of a series of disjoint elements and is not intended to be representative of any actual modeling situation Two SETs are defined in the Case Control Section The members of SET 100 are the IDs of elements that are to be retained on the reduced op2 element connection geometry data block This SET ID is specified as the value of the OELMSET parameter and is entered in the Bulk Data Section using a PARAM Bulk Data entry It is also referenced by the FORCE Case Control command The members of SET 200 are the IDs of grid points that are to be retained on the reduced op2 grid point geometry data block This SET ID is specified as the value of the OGRDSET parameter and is entered in the Bulk Data Section using a PARAM Bulk Data entry also It too is also referenced by the DISP Case Control command Note These PARAM entries could be placed in the Case Control Section instead of the Bulk Data Section Example files mass dat and mass bs dat can be fou
50. in Chapter 2 1 of the MSC Nastran 2004 Release Guide A fragment of the dr2mtch1 input file is provided to illustrate the use of the new MATCH function DRESP2 500 DIFM1 MATCH LS DTABLE TRI TR2 TR3 DRESP1 511 512 513 DTABLE TRI 1432e 2 TR2 1 741 1 6 381 1 SOL 200 easily solves this oversimplified design task The dr2mtch2 file is for the same design task except that now the beta method is applied to assist in the match M 6 3 Transformation of Approximate Optimization Task to a Feasible Design Introduction A parameter has been added to the DOPTPRM entry that transforms an infeasible optimization task to a feasible one Benefits A general statement can be made that optimization algorithms perform best when the design task does not include violated constraints In fact some algorithms will fail if a feasible design does not exist the algorithms used in MSC Nastran search for the best compromise infeasible design so that the transformation to a feasible design is not a strict requirement In order to facilitate the use of a general optimization procedure such as the ADS code which has been installed in MSC Nastran 2005 a simple transformation technique has been developed to ensure that the optimization task always works in the feasible domain Theory The standard optimization task minimizes an objective subject to satisfying a set of constraints The transformed problem designated the Method involves cre
51. in binary output file Flag determining coordinate of output stress and strain tensors Flag determining if more than one output state can be written to d3plot files Number of beam integration points for output CHAPTER 2 27 Nonlinear Analysis DYDCOMP Flag controlling elimination of rigid body output DYSHGE Flag controlling output hourglass energy density DYSTSSZ Flag controlling output of shell element time step and mass DYN3THDT Flag controlling output of material energy DYNINTSL Number of solid element integration points for output Example Projectile Hitting a Plate with Failure One typical example of SOL 700 Phase 1 is a projectile hitting a plate at an oblique angle The initial velocity of the projectile is large enough that over time various elements in the plate fail Depending on the postprocessor used if it can account for failed elements the failed elements are removed from the model This model involves contact between the projectile and the plate SOL 600 style contact is used It also involves the use of LS Dyna material MATD024 elasto plastic material with arbitrary stress strain curves and strain rate dependency This problem takes about 20 minutes to run on a 2 4 GHz PC The following plots show various time slices for the analysis 28 ara m CU ROI dem iaa Emmas sd ese mmu d iasi 81 EL arl Wap EH 5 Tea
52. input data are described in the compatible MSC Nastran Quick Reference Guide and summarized above Note that it was only necessary to add 1 to the Case Control a few new Bulk Data parameters and a few contact entries to the Bulk Data to an existing file that would be used in MSC Nastran SOL 101 106 109 or 129 analyses Example Pickup Truck Crash Test Another example involves crash testing of a pickup truck against a rigid wall The input data file for this example is quite large and can be provided on request Itisa typical example of what can be done using a full car or truck model developed originally for NVH analysis in SOL 700 for crash simulation 32 Where Can Find More Information MSC Nastran Explicit Nonlinear Analysis SOL 700 is documented in the following manuals and guides e MSC Nastran Quick Reference Guide e MSC Nastran Explicit Nonlinear User s Guide e MSC Patran User s Guide MSC Patran MSC Nastran and MSC Dytran Preference Guides LS Dyna Keyword User s Manual Version 970 available from LSTC e LS Dyna Theoretical Manual available from LSTC MSC Dytran Reference Manual e MSC Dytran Theory Manual 2 2 CHAPTER 2 33 Nonlinear Analysis MSC Nastran Implicit Nonlinear SOL 600 Between the release of MSC Nastran 2004 and MSC Nastran 2005 there have been many improvements a few new capabilities have been added and several errors have been corrected This section sum
53. is a continuation of the solution of its previous STEP Note that it is not legal to assign two different keywords NLSTATIC and NLTRAN of ANALYSIS in one SUBCASE The following is a typical example SUBCASE 1 This line can be omitted ANALYSIS NLTRAN TSTEPNL 200 STEP 10 DLOAD 10 STEP 20 DLOAD 20 STEP 30 DLOAD 30 Multiple SUBCASE s may be executed job where the types of analysis loads and boundary conditions can be changed All SUBCASEs are independent from each other i e no load history information is transmitted from one SUBCASE to the next At the start of each SUBCASE the deflections stresses and strains throughout the model are zero In each SUBCASE there can have different type of ANALYSIS For example 46 SUBCASE 1 ANALYSIS NLSTAT This line can be omitted NLPARM 100 STEP 110 LOAD 110 STRP 120 LOAD 120 SUBCASE 2 ANALYSIS NLTRAN TSTEPNL 200 STEP 210 DLOAD 210 STEP 220 DLOAD 220 In above example the solutions of SUBCASE 1 and SUBCASE 2 are independent of each other In case that the solution divergence is detected in a step MSC Nastran will terminate the solution of the current subcase and jump to the next subcase if it exits A case control command placed below the step level allows that command to vary from on step to another If it is placed above the step level the command remains constant for all steps in the subcase Most of the c
54. m Summary of Data Block Changes from MSC Nastran 2004 to MSC Nastran 2005 251 m More Stringent Case Control Check 253 MSC Nastran Release Guide 255 Preface E List of MSC Nastran Books Technical Support B Internet Resources List of MSC Nastran Books Below is a list of some of the MSC Nastran documents You may order any of these documents from the MSC Software BooksMart site at www engineering e com Installation and Release Guides L1 Installation and Operations Guide LJ Release Guide Reference Books T Quick Reference Guide 1 Programmer s Guide LI Reference Manual User s Guides LJ Getting Started LJ Linear Static Analysis Basic Dynamic Analysis Advanced Dynamic Analysis LJ Design Sensitivity and Optimization Thermal Analysis Numerical Methods LJ Aeroelastic Analysis LJ Superelement L1 User Modifiable LJ Toolkit Technical Support Web Phone and Fax Email For help with installing or using an MSC Software product contact your local technical support services Our technical support provides the following services Resolution of installation problems Advice on specific analysis capabilities Resolution of specific analysis problems e g fatal messages e e Advice on modeling techniques e e Verification of code error If you have concerns about an analysis we suggest that you contact us at an early stage You can reach technical
55. may take excessive computer time in some cases The first method is the classic method of solving static problems using explicit analysis techniques New entries have been added to MSC Nastran to make it easier to describe crash and impact Examples are the new TICD entry that adds a from thru by grid ID description so that initial velocity input can be described by one line rather than numerous Grid point lines This allows an input file setup for something else to be edited and quickly changed to a crash analysis For those familiar with the LS Dyna material descriptions about 25 of the most important and commonly used LS Dyna materials may be input to SOL 700 directly 8 Contact is described using the same entries as SOL 600 however there is a new entry to easily describe a rigid wall used for car crash simulation That entry is the MSC Dytran WALL entry see new entry section below In addition for those familiar with MSC Dytran several important MSC Dytran Parameters have been added Description of the SOL 700 Executive Control Statement Format SOL 700 ID PATH COPYR OUTR STOP NP NOERROR Example SOL 700 129 3 OUTR OP2 4 700 129 request nonlinear transient dynamics path 3 requests use of the dytran Isdyna script outr op2 requests that an op2 file np 4 requests that 4 processors be used Summary SOL 700 is a new Executive Control statement like SOL It normally activates an explicit nonlin
56. nonlinear static analysis In other words when there is no TTEMP and TMPSET in the Bulk Data file the TEMP LOAD will refer to the TEMP or TEMPD directly and a linear interpolation scheme will be used to determine the temperature filed in any specified time User should only set one temperature set SID in each STEP but this rule is only forced in the nonlinear elements To all the linear elements user can still use DLOAD bulk data entry to combine multiple TLOAD1 and TLOAD2 s whose EXCITE ID reference thermal load to support multiple sets of temperature loads this is also known as static load for dynamics to the temperature loads However it is user s responsibility to explain the physical meanings Note that all the upper stream superelements and all linear elements in the residual are still used the original concept static load for dynamics to input the thermal effect when ANALYSIS NLTRAN in SOL 400 The TEMP LOAD and all its corresponding temperature related bulk data entries introduced above can only describe the thermal effect to the nonlinear elements in the residual If there is no DLAOD Case Control command to define the temperature load in the static load for dynamics way the temperature effect to the linear part of the structure will be lost Outputs The outputs are requested by using the Case Control commands existing output requesting Case Control commands such DISPLACEMENT VE
57. of the subcase specific filename suffix respectively The modified ASSIGN and POST command are shown below followed by a small example illustrating the use of the above commands In this example the results re directed for both subcases are redirected to use specified files CHAPTER 9 227 Miscellaneous POST Post Processor Data Specifications Controls selection of data to be output for post processing functions via the OUTPUT2 module interface for selected commercial post processor products Another feature is to redirect F06 output file results for a subcase to a user defined file Format POST TOFILE furn ppname oplist TOCASE filename Examples POST TOFILE 51 PATRAN NOSTRESS POST TOFILE SUBCASE8 POST TOCASE SUFNAME1 Describer Meaning TOFILE Keyword to specify the destiny of output files No default if it appears above all subcases TOCASE Keyword to specify the destiny of subcase results to user defined output files No default if it appears above all subcases furn Fortran file unit reference number where data will be written Integer gt 0 filename Suffix filename see Remark 8 Char8 ppname Name of the target post processor program Default PATRAN oplist Names of output items to be processed Remarks 1 The POST Case Control command controls the placement of output data on external fortran files for use by commercial post processors Use of the POST command generates the proper value for the POST D
58. power law hardening CHAPTER 2 25 Nonlinear Analysis MATD077 LS Dyna material 77 General Christensen rubber model MATDO080 LS Dyna material 80 Ramberg Osgood plasticity MATDO081 LS Dyna material 81 Elasto visco plastic with arbitrary stress strain curve MATD100 LS Dyna material 100 Material for spot welds MATD127 LS Dyna material 127 Arruda Boyce rubber MATD181 LS Dyna material 181 Simplified rubber and foam model RBE3D MSC Dytran style RBE3 TICD Initial conditions like TIC with from thru by incrementing WALL Rigid wall Summary of New Bulk Data Parameters for SOL 700 DYENDTIM Determines how to translate TSTEPNL to MSC Dytran DYMATS1 Determines how to translate MATS1 to MSC Dytran DYLDKND Designates type of stress strain curve DYCOWPRD ID of Cowper Symonds strain rate equation DYCOWPRP P in Cowper Symonds strain rate equation DYNAMES Control of output file names d3plot or jid dytr d3plot DYSTATIC Method to simulate static analysis see above three methods DYBLDTIM Number of seconds a static load is built up DYBULKL Value of the linear coefficient in the bulk viscosity equation DYINISTEP Initial time step DYCONSLSFAC Default scale factor for contact forces DYCONRWPNAL Scale Factor for rigid wall penalty value DYCONPENOPT Penalty stiffens option DYCONTHKCHG Whether or not shell thickness change is considered in contact DYCONENMASS Treatment of mass of eroded grids DYCONECDT Time step size f
59. running of the program Some circumstances where you may need to run independently on MSC Nastran The Fortran program is on a classified computer but MSC Nastran is not You have a different version of the Fortran program You have a metric DDAM program You can use a PARAM entry to skip the Fortran part of the run run the Fortran elsewhere then restart the MSC Nastran run with the externally calculated f13 file PARAM MODEOUT YES This calculates modes outputs the required DDAM data then exits MSC Nastran 168 Use PARAM UHVOLD YES This runs MSC Nastran as usual but does not run the Fortran program Instead it will red a f13 file that has been prepared This parameter can be used a restart from a MODEOUT run where the f13 file was calculated externally It may also be desirable to replace the MSC Fortran program delivered with DDAM with a site developed one If so it is necessary to replace the ddamish exe program in the MSC Nastran installation with your program Because there are issues with arguments using some Fortran compilers contact MSC for instructions on what is needed to use this approach 8 2 CHAPTER 8 169 DDAM Processor Guidelines for Effective DDAM Analysis In addition to the usual guidelines for effective structural dynamic modeling and analysis several specific considerations are recommended for DDAM analysis The present discussion addresses the structural modeling foundation modeling a
60. set up to perform linear or nonlinear static analyses such as SOL 101 and SOL 106 Because of the numerical integration approach used within LS Dyna very small time steps are required to maintain accuracy and solution stability The penalty for taking small time steps is partially offset by not having to decompose a stiffness matrix See the upcoming MSC Nastran Explicit Nonlinear User s Guide for further theoretical details The small time step requirements are not a great problem when simulating events that occur quickly such as impact or crash However for longer events such as low frequency dynamics or static analysis the run time sometimes is too great for explicit methods and implicit analyses need to be employed SOL 700 has three ways of solving static problems Dynamic relaxation The input is applied as a step function and large damping is added The solution is run until approximate steady state values are obtained Slow buildup The static load is ramped slowly from zero to full value over a period of time long enough that no important natural frequencies are excited No extra damping is added Slow buildup with extra damping This method is like the previous method except that some extra damping is added thus the final run time can often be reduced Which method to use depends on the problem being solved and whether extra damping affects the solution or not The second method produces the exact results but
61. shape When idealized in MSC Nastran this creates situations where adjacent elements may not contain the same number of plies nor will these plies necessarily be continuous in terms of the internal ply numbering scheme Therefore the interpretation of results is a laborious task of manually identifying the consistent ply results when post processing the output To address this limitation user specification of global ply IDs has been introduced for easy reference of individual ply results across panels or sets of elements A new composite property entry called PCOMPG is available for the specification of global ply IDs The PCOMPG entry is an alternate property definition to the PCOMP entry The global ID for each ply is included in all ply result tables Optionally ply layer results can be sorted by global ply ID for a given element SET for easier results interpretation A new Case Control command called GPRSORT is introduced to reference an element SET Results are sorted by element ID or by global ply ID for a given element set This capability is available in all solution sequences that support composites except Design Optimization SOL 200 The following example illustrates the use of the PCOMPG Bulk Data entry to define global ply IDs The input file of this example and others can be found in the Test Problem Library pcompg dat Shown in Figure 4 1 is a laminated composite strip model with ply drop off A complete listing of
62. the U displacement set the dynamics of an undamped linear static structure subjected to foundation excitation is described by M M K SAU Ui We Sir Pu 8 3 M M U Ky U r r Where M M and M are mass matrix partitions K and K are stiffness matrix partitions and F is the foundation interface reaction set Since the foundation U is determinate due to Eq 8 1 the transformation of the U set into base fixed displacement patterns and rigid body motions respectively is introduced Rigid body motions are readily defined on the basis of the stiffness matrix by imposing the requirement that the U set produces no static reactions due to applied foundation motions U i e Rg Kj tU 0 Eq 8 4 Or 174 0 Kyl Eq 8 5 A convenient set of base fixed displacement patterns consists of a truncated set of base fixed unit mass normalized modes that are the solutions of Kul o Mj 6 3697 Eq 8 6 Assembling the truncated set of modes into the matrix 9 1 the desired variable transformation is defined as 1 1 ios 100 4 Ky Ka Ku Kil 41 0 1 8 7 d rl 1 T CITY rl rr 4 Upon transformation of the dynamic equation set Eq 8 3 with Eq 8 7 including pre multiplication by the transpose of the transformation matrix the modal equation set is of the form I P ee 2 uP ir a 1 1901 4 _ 0 Eq 8 8 P Mr
63. this model TPL testdeck pcompg1e dat shown in Listing 4 1 illustrates specification of global ply IDs for each laminate on the PCOMPG entry Also ply results sorted by global ply IDs are requested using the new GPRSORT Case Control command for element SET 100 includes elements 100 and 200 The standard ply results output is shown in Listing 4 2 with the global ply IDs reported under the PLY ID label Listing 4 3 shows the ply results sorted by global ply IDs for the defined element SET 100 84 Element 100 Element 200 Element 300 Figure 4 1 Laminated Composite Strip model with ply drop offs nastran system Listing 4 1 TPL testdeck pcompg1 dat 361 1 id msc pcompgle dat time 60 sol 101 cend title Composite Strip with Global Ply IDs disp all stress all set 100 100 gprsort 100 force all spcforces all 1 load 1000 begin bulk param k6rot 0 0 pcompg 1 5000 1 1 0054 4 1 0054 f 5 1 0054 6 1 0054 7 1 0054 7 8 1 0054 pcompg 2 5000 7 1 1 0054 7 3 1 0054 4 1 0054 5 1 0054 j 6 1 0054 8 1 0054 pcompg 3 5000 200 45 yes 90 yes 90 yes 0 0 yes 45 yes 45 yes FE 117040 45 yes 0 0 yes 90 yes 90 yes 0 0 yes 45 yes ap 00 5 CHAPTER 4 Elements 1 1 0054 45 yes 7 2 1 0054 45 yes 7 3 1 0
64. to reduce the amount of output produced When magnitudes are selected the component values are ignored Only a single positive value for f can be supplied and comparisons are performed in the global reference frame Comparisons are performed after the SET intersection is performed against the domain Selection of this option does not effect the MAXMIN GRID operations Scalar comparisons are performed using the minimum of all supplied values for the filters Complex values filters are performed on the Magnitude when components are selected Complex vector magnitudes follow a derivation using a deterministic interpretation for frequency response CHAPTER 9 225 Miscellaneous 2 When using filters the compound usage of the verbs PRINT PLOT is allowed The entries in the printed output are the entries that exceed any threshold while the remaining entries within the SET are marked as plot to allow for post processing operations When SORT is selected then print plot must be used to allow for table transpose operations to occur When any entry in the SORT2 format is above the threshold all values for time or frequency will be printed for the grid K 9 12 Write Results Recovery for Subcases into Separate F06 Files Recovery results written to the F06 output file can now be redirected to separate output files for each subcase Inputs Both the ASSIGN and POST commands are modified for assigning the physical filename and specification
65. variation on minimization of the maximum response technique described above The objective is to minimize a spawned design variable F Xg CiXp Subject to r r yXg s L SYXg jf L2 m r J CHAPTER 6 119 Optimization Because can become small it is necessary to offset the constraint in a fashion similar to the BETA method given above Define And then determine and Rmin the maximum and minimum values of R The y quantity can then be determined from user specified values of C and C using the following equation nay R min YXg EAS 2 Input The new features use the existing DRESP2 entry with additional options provided for the FUNC attribute Additionally the user can specify three constants that are used in the two algorithms All of these changes appear on the parent line of the DRESP2 entry which now has the following form 1 2 3 4 5 6 7 8 9 10 DRESP2 RID Label EOID Region Method C1 C2 C3 FUNC The modified or added terms are in italics There are two FUNC types FUNC BETA indicates that the DRESP2 specifies a min max problem and converts the problem as shown in the Theory on page 117 This DRESP2 can only be invoked by a DESOBJ case control entry The continuations on the DRESP2 can only supply DRESPI data as shown in the examples section The METHOD field in this case can be MIN default or MAX maximize th
66. wdir tmp dyna For the above example MSC Nastran will create the a command similar to the following to spawn dytran Isdyna assuming your input file is named abcd dat users joe sol700 run_dytran exe users joe sol700 dytran lsdyna jid abcd dytr nproc 4 memory 20m steps 2 wdir tmp dyna 14 If PATH is not specified a special version of dytran lsdyna will normally be used This version will be located in a subdirectory named dyna machine below the MSC Nastran base directory MSC BASE The machine directory will be aix alpha hpux etc If BASE is not available for a particular computer system PATH 1 2 or 3 must be specified STOP STOP is an optional item STOP is used to prevent execution of dytran lsdyna or prevent execution of MSC Nastran after IFP if so desired DO NOT ENTER any of the STOP options if any of the OUTR options are entered as the DMAP generated automatically by MSC Nastran will put an EXIT in the proper place The various options are as follows STOP 1 If STOP 1 MSC Nastran will be gracefully stopped after IFP This option is used to prevent MSC Nastran from performing its own solution normally used when the solution is performed by dytran Isdyna with ID 129 STOP 3 If STOP 3 MSC Nastran is stopped after and dytran lsdyna is not executed This would be the normal STOP option if the user wants to examine a dytran lsdyna input file make some changes and then execute dytran lsdyna manually
67. when the topology optimized element density values are written to the topology element density history file jobname des This file can be written in one of two formats The first format is a MSC Patran neutral element results file that can be used with a custom template file res tmpl to display topology results on MSC Patran This format is obtained by default In order to support MSC Nastran OptiShape users this file can also be written in OptiShape Patran Preference format by setting PARAM DESPCH1 1 Thus MSC Nastran OptiShape users can display CHAPTER 6 141 Optimization and animate SOL 200 topology optimization results using the MSC Nastran OptiShape Patran Preference Figure 6 6 shows and element density history file using the OptiShape Preference format DENSI Flag for element density file 1 Design cycle ID pa External element ID and density value CO O O 0 oO P2 SB a B BRB mn Figure 6 6 Element Density History File jobname des Guidelines and Limitations The quality of the results of a topology optimization task is a strong function of how the problem is posed in MSC Nastran This section contains a number of tips that have been developed based on extensive testing of this new capability A new DRESP1 COMP is introduced to define the compliance of struct
68. with multiple frequency content The new capability includes static loads and models the lift off phenomenon important in the design of free floating dampers Squeeze Film Damper Model Imbedded in MSC Nastran Transient Solution In a coordinated effort between GEAE and MSC the general SFD model was incorporated in MSC Nastran for transient analysis This was accomplished by inserting the SFD forces in the right hand Force Vector side of the equations of motion no special element was added to MSC Nastran GEAE provided MSC with the SFD FORTRAN code a description of the input output data the variable definitions and a checkout two degree of freedom test model and results The SFD code lends itself to a form of a NOLIN type of element similar to NLRGAP The NOLIN approach works with the NASTRAN time domain solutions SOL 109 and SOL 129 The new SFD elementis called NLRSFD The Bulk Data entry NLRSFD is used to input the SFD data journal diameter land length oil viscosity etc As with the NOLINS the NLRSFD will be selected by the NONLINEAR Case Control command The SFD code uses as input the relative displacements and velocities x x y y at the connecting grids and outputs the forces x and F x acting on the SFD damper journal grid point Equal and opposite forces F x x y and F x x y are applied to the stator SFD housing grid point CHAPTER 7 151 Rotor Dynamics Referring t
69. 00 00 000000 00 000000 00 000000 00 000000 00 000000 00 000000 00 000000 00 000000 00 WE GENERALIZED STIFFNESS 881936 04 011059 05 524259 06 816615 06 175493 07 435711 07 506449 07 003539 07 442988 08 5 4 CHAPTER 5 Dynamic Analysis 109 Enhancements to Dynamic Excitation Processing in DPD Module The DPD module generates dynamic excitations applied loads and enforced motion information for subsequent use in frequency response and transient response calculations Prior to MSC Nastran 2005 these excitations were generated in single precision and were stored in the Dynamic Loads Table DLT Starting with MSC Nastran 2005 these excitations are generated in machine precision Further these excitations are no longer stored in the DLT but are instead generated and held as machine precision matrices There is another important enhancement in the DPD module Depending upon the time delays and phase angles specified the columns of the excitation matrices are segregated appropriately so that each column represents a dynamic excitation with its own unique combination of time delay and phase angle This scheme allows for the residual vectors computed in modal dynamic analysis to be more meaningful and more representative of the dynamic excitation employed in the analysis since it accounts for the time delays and phase angles associated with the
70. 005 is another new nonlinear solution sequence SOL 400 Offered initially as a beta release SOL 400 will embody the current MSC Nastran nonlinear capabilities of solution sequences 106 and 129 into a single solution sequence Numeric Enhancements A new domain decomposition method is now available in beta form for the Automated Component Mode Synthesis capability which improves performance of NVH types of analysis particularly for models with complex geometry You can experience further performance improvements with a new technique used in the calculation of frequency response quantities for large problems solved across a wide frequency range Matrix to factor diagonal reporting has also been improved for analyses that use the Lagrange Multiplier Technique CHAPTER 1 MSC Nastran 2005 Release Guide Elements Analysis of composite structures now extend to include temperature dependency for unsymmetric laminates Also post processing composite structures is now much easier with global ply results tracking particularly for areas where ply drop off is apparent For bar elements it is now possible to specify a torsional mass moment of inertia value and for both bar and beam elements a new option to specify lumped mass with no off diagonal terms has been added This version of MSC Nastran also introduces an arbitrary beam cross section beta capability allowing the specification of cross section shapes using points and further allowing th
71. 04 and MSC Nastran 2005 when INTOUT ALL or NO IN MSC gpf001a SOL 106 TIME 10 DIAG 8 15 CEND TITLE GPF001A NONLINEAR GPFORCE TEST PROBLEM SUBTI HEXA ELEMENTS AXIAL FORCES NLM LABEL NONLINEARITY ANALYSIS ITER SPCF ALL DISPL ALL SSTRESS PRINT PUNCH 10 GPFORCE ALL ESE ALL SPC 100 NLPARM 1 S L S UBCASE 10 OAD 100 KIPON UBCASE 20 OAD 200 BCASE 30 OAD 300 BCASE 40 OAD 400 UBCASE 50 LOAD 500 BEGIN BULK PARAM GRDEQ 0 PARAM LGDISP 1 G H O Eto E NLPARM 1 4 ITER 1 10 ALL SNLPARM 1 4 ITER 1 10 NO 5 5 8 NODE CHEXA MODE 5 5 200 5 50000 200 6 50000 200 7 50000 200 8 50000 5 300 5 10000 300 6 10000 300 7 10000 300 8 10000 5 5 500 5 10000 500 6 10000 500 7 10000 500 8 10000 5 GRID 1 2 GRID 3 100 5 100000 100 6 100000 100 7 100000 100 8 100000 0 0 400 5 10000 400 6 10000 400 7 10000 400 8 10000 L O O OG eue cue 4 oooo 1 1 0 1 0 0 1 0 O O Pe 0 0 0 0 Ea O O O O O
72. 054 0 0 yes 4 1 0054 90 yes 5 5 1 0054 90 yes 8 1 0054 45 yes 8 1 2 0 7 2 0 35 1 0 1 0 6 1 0 0 0 0 0 0 0 0 0 2 365 1 9565 13000 32000 12000 cquad4 100 1 1 2 6 5 cquad4 200 2 2 3 7 6 cquad4 300 3 3 4 8 7 Force ly Vy4l 0 0 0 0 14 0 Force ls Oyo 90 070 0 1 0 1 1 12345 1 5 Troad 1000017 107I grid 1 0 0 0 0 0 0 0 2 1430540 0 0 0 6 24505 0 0 0 0 0 grid 4 3 0 0 0 0 0 6 030060206 grid 6 120120040526 7 2 0 120 020 6 grid 8 3 0 1 0 0 0 6 param autospc yes param post 1 enddata Listing 4 2 Ply Results Output for Each Element in the Model STRESSES IN LAYERED COMPOSITE ELEMENTS QUADA ELEMENT PLY STRESSES IN FIBER AND MATRIX DIRECTIONS INTER LAMINAR STRESSES PRINCIPAL STRESSES ZERO SHEAR MAX ID ID NORMAL 1 NORMAL 2 SHEAR 12 SHEAR XZ MAT SHEAR YZ MAT ANGLE MAJOR MINOR SHEAR 100 1 2 84204E 03 1 02828E 03 7 92127E 02 6 67973E 00 3 12898 01 69 43 7 31044E 02 3 13928E 03 1 20412E 03 100 4 7 48335E 02 8 80371E 02 2 54907E 02 7 95162E 00 7 79520E 01 8 69 7 87298E 02 9 19334E 02 8 53316E 02 100 5 7 55171E 01 4 35131 02 1 69516 02 8 54160E 00 7 97555E 01 21 66 8 20804E 00 5 02440E 02 2 47116 02 100 6 3 89044E 02 7 66743E 01 8 41258E 01 7 62246E 00 7 54499E 01 9 93 4 03775E 02 9 14045E 01 2 47590E 02 100 7 1 72768E 03 2 22906E 02 3 51962E 02 4 97689E 00 4
73. 2 FORCEAX GENEL GRAV GRDSET GRID INCLUDE IPSTRAIN ISTRESS PNEU ETE NE 2 lt lt 20 Table 2 2 Bulk Data Entries Available in SOL 700 Bulk Data Entries Available in SOL 700 Fatal Error LOAD LSEQ 1 MAT2 MAT3 MATS MATDxxx Y New LS Dyna materials MATD20M Y New Rigid Material Merge MATEP N MATHE MATHED MATF MATHP MATS1 MATVE MATORT MATVORT MATVP MATG MFLUID MOMAX MPC MPCAX NLPARM udo statics NLRGAP NOLINi NTHICK gi nm A A 77 lt Z Z CHAPTER 2 21 Nonlinear Analysis Table 2 2 Bulk Data Entries Available in SOL 700 Bulk Data Entries Available in SOL 700 Fatal Error PANEL PBAR PBARL PBCOMP PBEAM PBEAML PBEND PBUSH PCOMP PDAMP PDAMP5 PELAS PELAST PGAP PHBDY PINTC PINTS PLOAD PLOAD1 PLOAD2 Y A 2 ZKK Z A A A K 2 Z PLOAD4 Y Continuation supported PLOADX1 N PLPLANE PLSOLID PMASS PRESPT PROD 22 PSHEAR PSHELL PSOLID PTUBE PVISC RBAR RBE1 RBE2 RBE3 RESTART RFORCE RLOADi RROD RSPLINE RTRPLT SLOAD SPC SPC1 SPCADD SPCAX SPCD SUPAX TABLED1 TABLED2 TABLED3 TABLES1 Table 2 2 Bulk Data Entries Available in SOL 700 Bulk Data Entries Available in SOL 700 Y Changed to RBE3D Y Y CID METHOD continuation line not supported N ZZ Z 2 ah Fatal Error CHAPTER 2 2
74. 29 In SOL 400 the solution algorithm is modified in the following areas Three new nonlinear iterations and stiffness update algorithm AUTO TSTEP or ITER and SEMI are added on the Bulk Data entry TSTEPNL Please see the TSTEPNL Additions on page 63 for the details of TSTEPNL Bulk Data entry The old method ADAPT is still supported The algorithm for load bi sections The algorithm for automatic time adjustment after converging at each time step The solution divergence processing The stiffness update strategy as well as the direct time integration method is selected in the METHOD field of TSTEPNL Bulk Data entry As mentioned above there are four options If the AUTO option is selected the program automatically selects the most efficient strategy to adjust the incremental time step perform the iterations update the matrix and use bisection Please note the incremental time step adjustment is performed before the start of a time step And bisection will be performed after solution iterations and stiffness updates when convergence cannot be achieved If the TSTEP option is selected the program updates the stiffness matrix every KSTEP iterations The bisection will be applied only when the convergence cannot be reach by updating matrix In this option no automatic time step adjustment will be performed If the ADAPT option is selected the program automatically adjusts the incremental time step If convergence can
75. 3 Nonlinear Analysis Table 2 2 Bulk Data Entries Available in SOL 700 Bulk Data Entries Available in SOL 700 Fatal Error TEMP Y TEMPD Y TIC TICD Y New with increment options TIC3 Y New MSC Dytran type entry TLOADI Y TLOAD2 Y TSTEP Y Changed to TSTEPNL TSTEPNL Y WALL Y New rigid wall entry Summary of New or Changed Bulk Data Entries for SOL 700 BCTABLE Contact table many new fields have been added for slaves CDAMPID Scalar damper connection CDAMP2D Scalar damper connection CELASID Scalar spring connection CELAS2D Scalar spring connection CSPOT Spot weld in the LS Dyna style replaces CWELD for SOL 700 CFILLET Fillet weld in the LS Dyna style replaces CWELD for SOL 700 CBUTT Butt weld in the LS Dyna style replaces CWELD for SOL 700 CCRSFIL Cross fillet weld in the LS Dyna style replaces CWELD for SOL 700 COMBWLD Complex combined weld in the LS Dyna style replaces CWELD for SOL 700 DAMPGBL Defines values to use for dynamic relaxation EOSPOL Defines equation of state to use for solids in combination with certain materials MATDO001 LS Dyna material 1 isotropic elastic MATD2OR LS Dyna material 2 orthotropic 24 MATD2AN MATD003 MATD005 MATD006 MATD007 MATD012 MATD013 MATDO014 MATDO015 MATDO018 MATDO019 MATD020 MATD20M MATD022 MATD024 MATD026 MATD027 MATD028 MATD030 MATD031 MATD054 MATD057 MATD059 MATD062 MATD063 MATD064 LS Dyna material 2 Anisotr
76. 3609 7 00 6 00 Seriesi Series2 5 00 Series3 4 00 Series4 X 3 00 Series5 Series6 2 00 i Series7 1 00 Series8 0 00 Series9 0 00 1 00 2 00 3 00 4 00 5 00 Series10 kest Figure 9 1 Reduced Frequency Sweep for A Test Deck Results in a Failure to Converge Message with the PK Method The PKS method simply sweeps across the k range with a series of complex eigenanalyses at each of the estimated k values A determination is made as to when the 45 degree line is cross and the corresponding flutter root is stored Benefits The FAILURE TO CONVERGE message is no longer issued while the other benefits of the PK method ability to deal with real roots better estimate of complex roots and use in optimization are retained Input The existing FLUTTER Bulk Data interface has been enhanced with additional input as given by the following table with the modified inputs indicated in bold 1 2 3 5 8 10 4 6 7 9 FLUTTER SID METHOD DENS MACH VEL IMETH OMAX N EPS VALUE s CHAPTER 9 201 Miscellaneous Field Contents METHOD PKS and PKNLS augment the existing K KE P K and PKNL methods See Remark 9 OMAX The maximum frequency for the frequency sweep in Hertz Real gt 0 0 See Remark 10 EPS The inverse of the number of equal reduced frequency steps used in the frequency sweep Real gt 0 0 Default 01 Remarks 9 The PKS and PKNLS method
77. 3E 09 26 32 5 93985E 02 1 51365 02 2 21310E 02 85 86 Listing 4 3 Ply Results Sorted by Global Ply IDs 1 GLOBAL PLY ID E ELEME 1 2 2 1 2 1 2 1 2 1 1 2 S x ID NORMAL 1 00 2 84204 03 00 2 81691 02 00 2 73870 03 00 7 48335E 02 00 1 27601E 02 00 7 55171 01 00 7 30090 02 00 3 89044 02 00 2 79715 03 00 1 72768 03 00 2 83923 03 00 3 93539 02 COMPOSITE STRIP WITH GLOBAL TEST GPRSORT PROCESSING GLOBAL PLY ID 1 FAILU THEO HILL HILL HILL HILL HILL HILL HILL HILL HILL HILL HILL HILL FATT DRE RE ELEMENT RY ID 100 200 200 100 200 100 200 100 200 RESSES IN LAYERED NT STRESSES IN FIBER AND MATRIX DIRECTIONS NORMAL 2 SHEAR 12 1 02828 03 7 92127 0 2 90048E 02 3 28924 0 1 10669 01 1 04747 0 8 80371 02 2 54907 0 8 43308 01 4 03806 0 4 35131 02 1 69516 0 7 11099 01 2 39860E 0 7 66743 01 8 41258 0 6 88072 01 8 83526 0 2 22906 02 3 51962 0 5 37783E 02 6 37984 0 2 43778 02 3 62750 0 PLY IDS CES FOR FP FAILURE INDEX FOR PLY DIRECT STRESSES STRAINS 0 0055 0 0008 0 0003 0 0012 0 0000 0 0004 0 0000 0 0001 0 0002 0 0012 0 0047 0 0013 2 2 2 2 1 2 1 1 1 2 2 2 L A COM P OSD ELEMENTS INTER LAMINAR STRESSES PRINCIPAL STRESSES ZERO SHEAR MAX SHEAR XZ MAT SHEAR YZ MAT ANGLE MAJOR MINO
78. 4 0 1 1 1 0 5 0 3 1 0 PSHELL 1 1 0 1 1 1 0 SPEI 1000 123456 1 6 11 16 21 ENDDATA 9 9 Caution Concerning MSC Access Application Development In anticipation of functional changes to the MSC Access data base organization changes to the Application Program Interface API are being introduced during the basic MSC Nastran 2005 release The changes occur in the user interfaces to the Open routines for the keyed objects These interfaces are OPENC Create a Keyed Object OPENR Read or Update a Keyed Object OPENSO Read a Keyed Object using Sequential Methods Parameters made obsolete during the MSC Nastran Version 66 releases are being reused and redefined DBFLOC Locate a Keyed Object within a Group of Logical Data Bases An additional parameter has been added The user application should now provide a destination variable for the returned information in the arguments to the DBFLOC OPENR and OPENSQ interfaces Usage of a constant could result in premature application termination due an attempt to modify protected storage The definition of the KEY variable in other interfaces has also changed however until production release of the new functionality along with an update MSC Access Users Manual the current application interface will remain functional and provide a correct interfaces to any existing and current 2005 created MSC Access data bases Updated pages for the interfaces from the MSC Access Users Ma
79. 5 45 YES 2 0045 0 YES 0045 45 YES 1 0045 90 YES 1 0045 90 YES 1 0045 45 YES 2 0045 0 YES 1 0045 45 YES 0045 90 YES 1 0045 0 YES 0045 0 YES 1 0045 90 YES 0045 45 YES 1 0045 45 YES 0045 90 YES 1 0045 90 YES 1 0045 45 YES 1 0045 45 YES 5 Pset smahcelem will be imported as pcomp 1 CQUAD4 73 1 79 76 113 112 CQUADA 74 1 76 77 114 113 CQUADA 75 T 77 78 115 114 CQUAD4 76 1 78 79 116 115 CQUADA 77 1 79 80 117 116 CQUAD4 78 1 80 81 118 117 GRID 662 8 3x 0 GRID 663 8 25 3 0 GRID 664 8 5 3 0 GRID 665 8 75 0 GRID 666 9 93 0 Loads for Load Case Default SPCADD 2 1 Displacement Constraints of Load Set cfff 5 T 123456 1 38 959 112 149 186 223 260 297 334 371 408 445 482 519 556 593 630 Default Initial Temperature TEMPD 1 70 3 250 Referenced Coordinate Frames ENDDATA PARAM COMPMATT YES invokes the temperature dependent composite capabilities for the composite QUADA elements in the model Absence of the EPSILONT parameter means that the default integral strain method of updating the smeared laminate properties is selected for this analysis This example with the associated bulk data include files can be found in the Test Problem Library shcntrl2 dat glepnast dat and nitnast dat CHAPTER 4 83 Elements Global Ply Results Tracking Idealization of large composite panels requires that each ply within a panel be accurately modeled with regard to stacking location and
80. 500 TMPSE 201 1 2 4 5 6 1 400 7 202 700 TMPSET 202 1 2 P 8 204 800 TMPSET 204 1 2 TEMP 9 402 900 TMPSET 402 1 2 4 5 m 00000 00000 00000 00000 79 7595 79 79 80 80 80 80 L Ty 81 81 81 81 TEMP T 1 1 2 TEMP 1 4 TEMP 1 5 TEMP 23 1 3 2 TEMP 3 4 TEMP 3 5 TABLED1 300 0 0 9875 TABLED1 310 0 0 9875 5 4 1 4 2 4 4 4 5 TABLED1 400 1 0 9876542 2 0 00000 00000 00000 00000 00000 00000 00000 10000 ENDT ENDT ENDT CHAPTER 2 Nonlinear Analysis 61 62 LED1 J D w i 9 i E ENDDATA awn 500 0 0 O00 OV NF 9875 Or NF ae NF NFR 9876542 Ow NF NFR 80 80 80 80 1 0 1 0 ENDT 81 81 81 81 80 80 80 80 1 0 1 0 ENDT 81 81 81 81 2 0 Teg ENDT 80 80 80 80 1 0 1 0 ENDT 81 81 81 81 CHAPTER 2 63 Nonlinear Analysis TSTEPNL Additions TSTEPNL Parameters for Nonlinear Transient Analysis Field Contents METHOD Method for controlling stiffness updates and direct time integration strategy See Rem
81. 7 88 97 126 84 g Mass 2 X2 4 850 4445 5 295 in V gt 435 2 87 38 522 6 in sec 101 04 44 46 145 50 This sample problem is provided as the d1 model in the sample files In the output note that directions 2 and 3 are all 0 as those degrees of freedom were constrained out Only the X direction results and X directed shock F A have any meaning 8 5 CHAPTER 8 185 DDAM Processor Format of Coefficient File The DDAM coefficient file contains the weighting factors used for the response calculations the directional scaling factors as well as the modal mass cutoff value The file is structured as shown below The default equations to which these apply are M is the modal weight in kips for that mode AA AB M AC M VA VB M Aor VC M For surface ship hull and shell mount the equation is AA AB M AC M A AF 0 AD M There is a complete set of AA AB AC and when needed AD weighting factors for each of the possible analysis configurations surface ship and submerged ship deck mount shell mount and hull mount In addition there is a trio of AF acceleration factors and VF velocity factors for each of these sets one for each shock direction There are additional factors for Elastic Plastic design The file is formatted sort of like an MSC Nastran file Each set of coefficients and factors are entered on a COEF entry that describes the applicability of that set of fac
82. 8 DRESP1 114 125 137 DRESP2 117 FLUTTER 200 54 MATSI 55 NLRSED 152 NSTEPNL 55 PBMSECT 96 PBRSECT 96 PUNCH 214 RADEC 223 SPC 213 SPCD 213 SUPORT 158 TMPSET 55 64 TOPVAR 136 TSTEPNL 63 TTEMP 55 64 WALL 8 INDEX Bulk Data Parameters AUTOOSET 198 BAILOUT 77 COMPMATT 81 COUPMASS 89 DESPCH 140 EPSILONT 81 FASTER 78 FKSYMFAC 54 FOLLOWK 54 LANGLE 54 LGDISP 54 54 MODEOUT 167 NDAMP 54 NLAYERS 54 NLPACK 54 NLTOL 54 OELMSET 208 209 OGRDOPT 208 OGRDSET 208 209 OMSGLVL 208 OPCHSET 208 PH2OUT 54 POST 160 SRCOMP 115 UHVOLD 168 ZROCMAS 102 C Case Control 253 Case Control Commands ADAMSMNF 198 ANALYSIS 45 54 ASSIGN 226 MODESELECT 103 NLRESTART 54 NLSTRESS 54 POST 226 227 STEP 45 54 SUBCASE 45 compliance 137 compute conjugate matrix multiplication 215 convergence criteria 47 crash simulation 31 c set masses 102 D Data Block DYNAMIC 251 2 251 GEOMA 251 RESP12 252 DDAM 157 DFREQ 128 DIAG 39 201 displacement output filters 224 Distributed Memory Parallel DMP 75 DMAP modules 242 DMIG 87 DOT optimizer 131 DPD module 109 Dynamic Design Analysis Method DDAM 158 dynamic excitation 109 dynamic relaxation 7 E Elasto Plastic material 67 Endian 204 ENDTIME 15 enforced displacement 213 enforced motion 110 error factors 47 Explicit Nonlinear SOL 700 6 External Superel
83. AM elements Inputs FMS SECTION NASTRAN SYSTEM 414 1 BULK DATA PARAM COUPMASS 1 Note This parameter may optionally be specified in the Case Control Section Outputs The resulting mass matrix for the BAR and BEAM element will only contain translation terms off diagonal and rotation terms will be zero Example The example file mass bs dat can be found in the Test Problem Library NASTRAN NLINES 99999 NASTRAN system 414 1 id msc mass bs dat 5 v2005 15 Jan 2004 5 SOL 101 DIAG 8 COMPILE SEMG ALTER ENDIF NOMGG 0 MESSAGE MASS MATRIX 6 MATGPRBGPDTS USETO MJJX G MGG EXIT 5 CEND TITLE MASS MATRIX FOR BAR BEAM ELEMENTS COUPMASS 1 BEGIN BULK PBAR 101 100 NE 01 01 202 10 102 100 2 1 01 401 02 10 1 100 10 PARAM COUPMASS 1 5 GRID 1 1 1 1 GRID 2 1 1 1 CBAR 101 11 12 a 2 A A 1 1 5 GRID 21 1 1 1 GRID 22 1 1 1 CBAR 2 101 21 22 T B B 2356 5 GRID 31 1 1 1 GRID 32 1 1 1 CBEAM 3 102 31 32 1 C C zI 1 5 GRID 41 1 1 1 GRID 42 1 1 1 CBEAM 4 102 41 42 1 D D 2356 GRID 51 1 1 1 GRID 52 1 1 1 SPOINT53 54 CBEAM 5 102 51 52 Ts E E 22356 F F 53 54 ENDDATA CHAPTER 4 91 Elements The default mass matrix is shown MJJX POINT VALUE POINT VALUE VALUE
84. ASSIGN statement with a UNIT describer then a new entry will be created in the FORTRAN unit tables 10 11 CHAPTER 9 Miscellaneous the default file name or d If the file name is omitted or specified as or if this is a second or subsequent ASSIGN statement for the same logical key UNIT combination on previously specified file name or default name if none was previously specified will be used Ifitis necessary to execute the INPUTT4 and OUTPUT4 modules on the same unit then specify ASSIGN OUTPUTA only The same is recommended for the INPUTT2 and OUTPUT2 modules STATUS UNIT and FORM are ignored if assigning a log name DBset member name FORM FORMATTED must be specified for a unit when ASCII output is desired from the OUTPUT4 DMAP modules that processes the unit and for Cray UNICOS when ASCII input is supplied to the INPUTT4 DMAP module that processes the unit See the MSC Nastran 2005 DMAP Programmer s Guide FORMAT NEUTRAL is selected on the DBUNLOAD and DBLOAD FMS statements that process the unit See the Database Concepts on page 513 of the MSC Nastran Reference Guide The neutral file format is desired for the OUTPUT2 module and for Cray UNICOS when ASCII input is supplied to the INPUTT2 module For the DBUNLOAD OUTPUT and OUTPUT4 modules binary format may be requested using FORM UNFORMATTED and for all platforms except Cray UNICOS using FORM BIGENDIAN FORM LITTLEENDIAN FO
85. ATURE LOAD 8 DISPLACEMENT SORT1 REAL ALL nlstress all stress all SUBCASE 4 analysis NLTRAN step 7 TSTEPNI 1 SPC 2 TEMPERATURE LOAD nistress all stress all step 8 TSTEPNI 1 SPC 2 TEMPERATURE LOAD 9 DISPLACEMENT SORT1 REAL ALL 10 DISPLACEMENT SORT1 REAL ALL nistress all stress all BEGIN BULK PARAI POST PARAI COUPMASS 1 PARAI LGDISP 1 PARAI K6ROT 100 PARAM NOCOMPS 1 PARAI PRTMAXIM YES PARAM COMPMATT YES CHAPTER 2 Nonlinear Analysis 59 60 PARAM EPSILONT PARAM NLTOL TSTEPNL 1 4 0 PCOMP 1 1 5 8 1 2 9 6 8 T 1 TABLEM1 1 CR 60 CS 120 CT 180 CU 250 CV 320 TABLEM1 2 CW 60 CX 120 cy 180 EX 50s DA 320 TABLEM1 3 BX 60 BY 120 BZ 180 CA 250 CB 320 TABLEM1 4 CM 60 CN 120 co 180 CP 250 CQ 320 5 TABLEM1 5 CC 60 CD 120 CE 180 CF 250 CG 320 TABLEM1 6 CH 60 CI 120 CJ 180 CK 250 CL 320 cquad4 1 1 1 INTEGRAL 0 25 1 AUTO 04875 7 1546 2 9 6 229 6 6 7 97 3 5 4 2 44 9 5 70 2 9 6 4 01 6 140 3 89 6 3 82 6 200 3 47 6 3 87 6 260 2 29 6 4 24 6 ENDT 6 6 70 6 76 1 341 5 140 12945 1 266 5 200 1 222 5 1 296 5 260 1 334 5 1 46 5 ENDT T LIFO TO 75 0996 7 11 6 140 7 08 6 7 06 6 200 7 05 6 7 04 6 260 7 05 6 7 08 6 ENDT 529 70 29 22 9 140
86. Analysis The first portion of the dmig002 file is as follows 2345678 2345678 2345678 2345678 2345678 2345678 2345678 2345678 234567812345 DMIG KAAX 0 1 2 0 324 DMIG KAAX 6 1 6 1 3 014712042 05 6 2 4 204709763D 08 DMIG KAAX 6 2 6 1 1 204709763 05 6 2 3 014712042D 05 DMIG KAAX 6 3 6 1 4 616527206D 04 6 2 4 616527206D 04 6 3 1 308497299D 05 DMIG KAAX 17 1 x 6 1 6 239021038D 04 x 6 2 2 528344607D 03 6 3 6 239758760D 03 17 1 5 939989945D 05 Temperature Dependent Stress Strain Curves MSC Nastran 2005 offers the capability of stress strain curve dependence as a function of temperature The user specifies these stress strain curves at different temperatures and then specifies the temperature to use for each subcase Linear interpolation between the supplied curves is used to determine the appropriate curve at the temperature specified for a particular subcase MSC Marc s AF Flowmat capability is used for this capability therefore user subroutines do not have to be supplied This capability is best explained with an example this example can be obtained from MSC Nastran development The name of the file is mattep20 dat SOL 600 NLSTATIC path 1 stop 1 TIME 10000 CEND ECHO NONE DISPLACEMENT plot ALL SPCFORCE PLOT ALL Stress PLOT ALL Strain PLOT ALL SPC 1 NLPARM 2 1 temp init 0 subcase 1 temp load 11 LOAD 100 subcase 2 temp load 12 LOAD 200 subc
87. B OPTION 1 USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 111 NOT PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 121 NOT PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 171 NOT PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 181 NOT PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 20001 NOT PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER FATAL MESSAGE 7759 MTM36A ELEMENT S IN SET 100 CONNECT S POINT ID 40001 NOT
88. BIS Number of bisections performed TIME STEP The ratio of the current time increment to the original DT on ADJUST the TSTEPNL Bulk Data entry ITR Number of iterations at each time increment ERROR FACTORS There are three error factors displacement load and works In DISP order for an increment to converge these factors must satisfy LOAD the error tolerance rules specified by CONV EPSU EPSP and WORK EPSP on the TSTEPNL Bulk Data entry CONV RATE Converge rate which denotes how fast the solution converges for the current increment A value of 0 0 means fast converges and a value 1 0 means that the solution will never converge ITR DIV Number of iteration divergence Action to correction solution divergence will be taken if ITRDIV MAXDIV MATDIV Number of material divergence 1 i e it will be 1 if there is no material divergence The material divergence is due to bad creep strain or excessive sub increments in plasticity 50 Table 2 4 Explanation of Information in Nonlinear Iteration Summary Table AVG R FORCE Average residual force In order for an increment to converge this value must become very small TOTAL WORK Accumulated total work done to the structure model This value is only an approximation DISP The average displacement the maximum displacement and AVG its grid point identification number and component number MAX AT GRID C TOT KUD Total number stiffness updates per
89. Bicycle Frame The input data for this example that is related to topology optimization is listed in Listing 6 2 The result shown in Figure 6 9 is similar to existing bicycle frames Listing 6 2 Input File for Example 1 Topology Optimization Example 1 XMY Sid msc topexl v2005 4 Jun 2004 xmy SOL 200 6 OPTIMIZATION CEND SEALL ALL SUPER ALL ECHO NONE set 7 20 set 9 40 DESOBJ 1 DESGLB 1 SUBCASE 1 SUBTITLE LOAD CASE 1 SPC 2 LOAD Eo DRSPAN 7 146 ANALYSIS STATICS SUBCASE 2 SUBTITLE LOAD CASE 2 SPC 2 LOAD 9 DRSPAN 9 ANALYSIS STATICS BEGIN BULK TOPVAR 1 TSHELL PSHE Ay ox gr 1 DRESP1 2 FRM FRMASS DRESP1 20 1 DRESP1 40 2 DRESP2 1 COMPL SUM DCONSTR 1 2 22 Figure 6 9 Topology result of Bicycle Frame References 1 Bendsoe M P and Sigmund O Topology Optimization Theory Methods and Applications Springer 2003 2 Rozvany G LN Bendsoe M P and Kirsch U Layout Optimization of Structures Appl Mech Rev 48 1995 pp 41 119 6 9 CHAPTER 6 147 Optimization BIGDOT Optimizer Introduction BIGDOT is an optimization algorithm that has been developed by VR amp D to solve large optimization tasks A guideline for the DOT optimizer the workhorse optimizer in SOL 200 is that it can comfortably address problems with several hundred design variables and c
90. D NEW YES YES SEQ Topology Optimization DBC out xdb 40 UNFORMATTED NEW YES YES DIRECT Database Converter Unit DBUNLOAD REQ 50 UNFORMATTED NEW YES NO SEQ DBUNLOAD FMS statement DBLOAD 51 OLD YES NO SEQ DBLOAD FMS statement Table 2 1 FORTRAN Files and Their Default Attributes continued Logical Key Physical Mee Fon Status Assignable Open fts Description Name Name Application out mnf none none Interface for ADAMS Flex A502LU Available for Use DBMIG Available for Use USER FILE Any User Defined File where Logical Key Name specifies the logical key NAME used on the ASSIGN statement Physical Name specifies the default name used to open the file i e the default filename2 name REQ means that this parameter is required in the ASSIGN statement from the user Unit No specifies the default FORTRAN unit number used by MSC Nastran REQ means that this parameter is required in the ASSIGN statement from the user Form specifies the default FORM used when the file is opened Status specifies the default STATUS used when the file is opened REQ means that this parameter is required in the ASSIGN statement from the user Assignable If YES the user may assign a physical file to this logical name If NO the unit if any and logical name are reserved by MSC Nastran Open If YES the file is opened by default If NO t
91. DR element performs more consistently and accurately for each of the four element mesh densities coarse to fine analyzed compared to the QUAD4 element that is less accurate for the models with larger element edge lengths and fewer elements 95 4 7 Arbitrary Beam Cross Section Pre Release Introduction Beam elements have long been a staple in MSC Nastran Over the years the capability of beam element has grown steadily from constant cross section of PBAR to variable cross section of PBEAM However users are required to compute the sectional properties in order to utilize BAR and or BEAM elements in the analysis To alleviate the amount of effort from engineers PBARL and PBEAML were added for popular cross sectional profiles Nevertheless engineers are still left to search for modeling alternatives for 1 D structural components with arbitrary cross sectional shapes A new user interface for describing cross section shapes for CBAR and CBEAM element types has been developed and will be provided in the release of MSC Nastran 2005 r2 and is currently available for beta testing Development of this new capability in MSC Nastran has been driven by the automotive industry keen to be able to easily represent the nonstandard beam profiles commonly used in automotive design and to use analysis tools to optimize the profile designs themselves Subsequent development phases are planned which will add more advanced features to the Ar
92. EC S N NONLFT S N NOTRL S NOEED SORTNLFT S N NOUE UNUSED12 SEID I 244 Output Data Blocks APPLOD Matrix of applied load amplitudes ENFLODK Matrix of equivalent enforced motion load amplitudes due to stiffness effects ENFLODB Matrix of equivalent enforced motion load amplitudes due to viscous damping effects ENFLODM Matrix of equivalent enforced motion load amplitudes due to mass effects ENFMOTN Matrix of enforced motion amplitudes ELTPRT ECT is always input in the 12st position and no longer input in the 4th position which is now occupied by the new data block NSMEST Format ELTPRT ECT GPECT BGPDT NSMEST EST CSTM MPT DIT CASSECC EPT UNUSED VELEM PROUT S N ERROR WTMASS Input Data Blocks NSMEST NSM Bulk Data entries in EST format UNUSED Unused and may be purged FA1 VREF parameter is now required input Format FA1 KHH BHH MHH QHHL CASECC EDT FSAVE KHH1 BHH1 MHH1 FLUTABP S N FLOOP S N TSTART S N NOCEAD LPRINT XYUNIT VREF CHAPTER 10 245 Upward Compatibility Output Data Block FLUTABP Flutter summary table for all methods except K and KE Parameters XYUNIT VREF FRLG Format FRLG Input integer default 0 FORTRAN unit number to which extracted khh1 values are written at each sweep point for the PKS and PKNLS met
93. ENC 2 Purpose Create new keyed object and return a logical file reference 3 Calling Sequence CALL OPENC DBNUM NAME WRDREC FILNUM KEYLEN CLSTER D3 D4 D5 D6 IRE T DBNUM Integer input Logical database number em k Array input Dictionary entry and keyed object name to create f logical i WRDREC Integer input Number of words per logical record in object Logical handl i FILNUM Integer output ogica andle number assigned to the object 219 220 KEYLEN Integer input The number of words in the key 0 gt Use Hierarchal Key Method n Use BBB Tree Method CLSTER Integer input Clustering Method 0 gt Use standard Key clustering algorithm 1 Re order keys for optimum entry storage D3 DA Currently unused In prior releases Integer input these arguments represented memory D5 D6 addresses for I O buffer work areas IRET Integer output Return code from the routine 0 gt Normal data block creation 1 Requested NAME already existed 2 gt Too many logical files open 4 Method NAME is checked to determine if it already exists The control area is checked to make sure that a new object can be opened and made available for processing If both conditions above are satisfied the buffer management area is cleared and the DAT control area as described in the DICENT routine description is created The primary map blocks and the first data
94. ES EXTRACTION ORDER WARNING MESSAGE THERE ARE NO Q SET DEGREES OF FREEDOM LEFT TO ACCOMMODATE ANY USER INFORMATION USER ACTION gt EIGENVALUE NP o D we 881936 04 011058 05 524259 06 816616 06 175494 07 435711 07 9144 5 4 BEFORE AUGMENTATION OF RESIDUAL VECTORS RADIANS CYCLES 1 371837 02 2 183346 01 5 487311E 02 8 733327E 01 1 234609 03 1 964941 02 2 194679 03 3 492940 02 3 428547 03 5 456702 02 4 935292 03 7 854762 02 NO RESIDUAL VECTORS WILL COMPUTED SPECIFY AT LEAST 6 MORE Q SET DEGREES OF FREEDOM RESIDUAL VECTORS GENERALIZED MASS 000000 00 000000 00 000000 00 000000 00 000000 00 000000 00 Mop as p GENERALIZED STIFFNESS 881936 04 011058 05 524259 06 816616 06 175494 07 435711 07 If we replace the OSETi SPOINT entries with PARAM AUTOOSET YES SOL 103 DIAG 8 15 CEND TITLE AUTOQSET DEMON SUBTITLE TWENTY CELL SPC 1002 METHOD 1 BEGIN BULK EIGRL 1 120 PARAM AUTOQSET YES GRID 10000 1 19 CBAR 101 100 1 18 100 1000 1 1000 5 1002 10020 ENDDATA STRATION PROBLEM BEAM 0 0 0 0 0 0 0 10000 10001 0 0 0 0 31416 0 15708 23 7 764 4 3 10000 3 0 1246 Then the results show that all of the eigenvectors
95. LOCITY ACCELERATION STRESS NLSTRESS OLOAD SPCFORCE etc are also allowed in the nonlinear transient analysis in SOL 400 Two special outputs Nonlinear Iteration Summary Table and PARAM PH2OUT which have been introduced in MSC Nastran 2004 are also available on the nonlinear transient analysis in SOL 400 In addition a new output control PARAM NLPACK is added in this release for nonlinear transient analysis only CHAPTER 2 53 Nonlinear Analysis This new parameter NLPACK 100 is the default is used to control the packed output in SOL 400 The value of NLPACK represents the total number of output time steps in one output package SOL 400 will process the output procedure only after collecting all NLPACK output time steps or at the end of each STEP case Note that NLPACK 1 means to collect all output times steps a STEP case and then output them all together which is the same as SOL 129 output method This parameter only used in ANALYSIS NLTRAN and restart is only possible at the end of each output time step To nonlinear static analysis ANALYSIS NLSTAT NLPACK is always equal to 1 User Interfaces The user interfaces which are important or new to the nonlinear transient analyses in SOL 400 are summarized in this section For details please refer to the MSC Nastran Quick Reference Guide NASTRAN System Cells e STPFLG SYSTEM 366 Selects the SUBCASE or STEP layout when there are a num
96. MAP parameter associated with the particular post processor All of the other parameter controls related to the POST DMAP parameter remain in effect and are described in Parameters on page 603 The products supported are identified in the following table PATRAN is the default post processor name used for ppname DBC output POST 0 cannot be controlled by the POST command 228 ppname Product PARAM POST Value PATRAN MSC Patran V3 SDRC SDRC IDEA S NF MSC LMS NF FEMTOOLS DDS FemTools UNIGRAHICS EDS Unigraphics 2 The TOFILE describer is followed by the specification of either a FORTRAN unit reference number or a file name associated with the external file that receives the output data If a FORTRAN unit number is used the file must be associated with it via the ASSIGN File Management Statement If POST appears above all subcases TOFILE must be used to specify either a FORTRAN unit reference number or a file name The default value of TOFILE which appears under a subcase will inherit from the value given in the POST above all subcases If the unit reference number is associated with a form formatted file changes in unit numbers across subcases are not allowed The data that can be controlled for each post processor product is limited and is identified under the description of the POST and related DMAP parameters in Parameters on page 603 The keywords that can be used for the oplist options are shown in the following
97. MODE parameters provide similar capability They are described more fully in section the following sections on special circumstances ENTER WEIGHT CUTOFF PERCENT OR RET FOR DEFAULT Default 80 0 This number is the percentage of total mass at which modal processing ceases The DDAM document specifies that only a percentage of the total modal mass needs to be included in the NRL sum The default value is specified in the program with the default coefficients or in the alternate coefficient file The value here should be entered as a percentage i e 80 or 100 not as a decimal Specifying 100 will process all the modes that were calculated by MSC Nastran Special Circumstances Selection of Specific Modes If the user wishes to selectively choose which modes go into the NRL summation a capability is provided using DMI Direct Matrix Input entries On the DMI entries the user describes a matrix called PARTNVEC which is a partitioning vector The vector is used to break up the eigenvector matrix and UHV matrix in a specific manner PARTNVEC is a multi row 3 column matrix where each row represents a mode number and each column represents a shock direction If the matrix has a 1 166 entry that particular mode is retained for that particular shock direction The following shows a PARTNVEC description employing several options that a user might be interested in for an analysis that
98. MSC Nastran 2005 Release Guide Corporate MSC Software Corporation 2 MacArthur Place Santa Ana CA 92707 USA Telephone 800 345 2078 Fax 714 784 4056 Europe MSC Software GmbH Am Moosfeld 13 81829 Munich Germany Telephone 49 89 43 19 87 0 Fax 49 89 43 61 71 6 Asia Pacific MSC Software Japan Ltd Shinjuku First West 8F 23 7 Nishi Shinjuku 1 Chome Shinjyku Ku Tokyo 160 0023 JAPAN Telephone 03 6911 1200 Fax 03 6911 1201 Worldwide Web www mscsoftware com Disclaimer MSC Software Corporation reserves the right to make changes in specifications and other information contained in this document without prior notice The concepts methods and examples presented in this text are for illustrative and educational purposes only and are not intended to be exhaustive or to apply to any particular engineering problem or design MSC Software Corporation assumes no liability or responsibility to any person or company for direct or indirect damages resulting from the use of any information contained herein User Documentation Copyright O 2004 MSC Software Corporation Printed in U S A Rights Reserved This notice shall be marked on any reproduction of this documentation in whole or in part Any reproduction or distribution of this document in whole or in part without the prior written consent of MSC Software Corporation is prohibited MSC 5 MSC Dytran MSC Marc MSC Nastran MSC Patran the M
99. NDT 00 10 25000 100 T 00 10 23000 100 00 10 21000 100 00 10 19000 100 00 10 9000 100 30000 28000 26000 22000 13000 33 1500 34 MT CHAPTER 2 39 Nonlinear Analysis CQUAD4 ENDDATA In this input the stress strain curves are specified by TABLES entries The collection of stress strain curves to be used is specified in the TABLEST entry and the corresponding temperatures at which they apply is specified in the TABLEMI entry The TABLEM1 ID is called out in field 7 of the MATT1 entry and the TABLEST ID is called out in field 5 of the MATTEP entry TABLEST must list the stress strain TABLESI IDs in order of increasing temperature and the first ID must be at the lowest temperature specified anywhere in the analysis In this example it is temperature of 70 corresponding to temp init 10 in the Case Control Similarly the temperatures in the TABLEMI entry must be in increasing order The stress strain curves should cover the entire range of temperatures for the analysis so that no extrapolation is needed The actual temperatures for each subcase are given by the temp load specifications for each subcase There is one parameter that is critical to this analysis param mrafflow mymat0 Name of the file containing temperature dependent stress versus plastic strain curves in MSC Marc s AF_flowmat format This file can be generated from the current MSC Nas
100. P1 entries that have RTYPE s that are associated with grid responses in a frequency response subcase i e FRDISP FRVELO or FRACCL Benefits Residual vectors became the default in MSC Nastran 2004 and often show dramatic improvements in dynamic response analyses This benefits SOL 200 and the new RESVEC option creates residual vectors that are ideal for obtaining accurate sensitivity values in modal frequency response sensitivity analysis Input No new input is required for this new feature but optional describers have been added to the RESVEC Case Control command ADJLOD NOADJLOD Control calculation of residual vectors based on adjoint loads in a modal frequency response sensitivity analysis Default ADJLOD See the MSC Nastran Quick Reference Guide for a complete description of the RESVEC Case Control command Outputs There are no new outputs Guidelines and Limitations Residual vectors from adjoint loads are only applicable in SOL 200 when ANALYSIS MFREQ If there are FREQ3 4 or 5 entries to specify excitation frequencies the residual vectors based on adjoint loads will not be computed automatically In this case the user can generate these residual vectors by using the RVDOF or RVDOF1 entry with grid and components the same as those entered on the DRESPI entry 126 Example rvadjsens dat A structural model that represents a sensor on a missile is shown below The objective is to minimize the jitter at
101. PH 26 DYNEIPS 26 DYNINTSL 27 DYRBES 26 DYRLTFLG 26 DYSHELLFORM 26 DYSHGE 27 DYSHNIP 26 INDEX 259 DYSHTHICK 26 DYSIGFLG 26 DYSTATIC 25 DYSTEPFCTL 26 DYSTRFLG 26 DYSTSSZ 27 DYTERMNENDMAS 26 DYTSTEPDT2MS 26 DYTSTEPERODE 26 Explicit Nonlinear 6 ID 9 NOERROR 15 NP 14 STOP 14 SPC 213 SPCD 213 spot welds 74 Squeeze Film Dampers SFDs 150 stiffness update strategy 48 structure modes 103 Subroutines DBFLOC 218 OPENC 219 OPENR 220 OPENSQ 222 System Cell ORMETH 92 System Cells 414 89 ITRFMT 401 53 STPFLG 366 53 TZEROMAX 373 53 T temperature excitation 51 temperature dependent composites 80 Temperature Dependent Stress Strain Curves 37 thermal results 223 time integration method 48 Topology optimization 135 Torsional Mass Moment of Inertia 88 transient response 110 TRLG module 110 I INDEX U unsymmetric laminates 80 V Variable Endian 203 W work error 47
102. PRESENT IN GRID SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ALL POINTS CONNECTED TO ELEMENTS IN ELEMENT SET PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER WARNING MESSAGE 7760 MTM36A GRID SET 200 CONTAINS POINT ID 5 NOT PRESENT IN THE MODEL USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ONLY POINTS ACTUALLY IN THE MODEL PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 USER WARNING MESSAGE 7761 MTM36A GRID SET 200 CONTAINS POINT ID 1005 NOT CONNECTED TO ANY ELEMENTS IN SET 200 USER ACTION MAKE SURE THAT THE GRID POINT SET CONTAINS ONLY POINTS ACTUALLY IN THE MODEL PROGRAMMER INFORMATION MATMOD OPTION 36 SUB OPTION 1 The fatal messages inform the user that grid points 21 22 111 121 171 181 20001 and 40001 are connected to elements in set 100 the OELMSET and that they are not present in set 200 the OGRDSET The user is also warned that grid point ID 5 in set 200 is not a model grid point In addition a warning is issued for point 1005 in set 200 This point was not connected to any of the elements in set 100 The user has requested that the element related set of grid points be punched This set of grid IDs is punched in Case Control SET format as shown SET 200 1 THRU 4 21 22 111 121 171 181 20001 40001 211 212 If the above SET 200 is used to replace the existing SET 200 definition then the element set and grid point set would be consistent and the
103. QUAD4 110 100 10900 10901 11001 11000 CQUAD4 111 100 11000 11001 11101 11100 CHAPTER 2 57 Nonlinear Analysis CQUADA 112 100 11100 JT ON 11201 11200 5 PSHELL 100 100 0 10 100 101 5 5 200 16 11200 11201 5 200 26 10000 10001 5 5 400 16 11200 11201 5 400 26 10000 10001 5 400 1 10700 5 400 2 10701 5 ENDDATA Example 2 Example two EX02 is modified from the standard QA file NLTSUBO2 It shows two different types of analyses in the same job This model is similar to the Example one except adding some static loads and NLPARM s All the bold font statements are entries that show difference in two different types of analyses ID MSC EX02 5 TIME 150 5 SOL 400 5 CEND TITLE TEST MIXED ANALYSES NLSTAT AND NLTRAN EX02 SUBTITLE SPC CHANGE IN THE STEPS IN EACH SUBCASE SET 10 10000 11200 SET 20 101 SEALL ALL DISPL ALL STRESS 20 SUBCASE 100 ANALYSIS NLSTAT STEP 10 LOAD 800 SPC 200 NLPARM 110 STEP 20 LOAD 900 SPC 400 NLPARM 120 5 SUBCASE 200 ANALYSIS NLTRAN STEP 10 DLOAD 100 SPC 200 TSTEPNL 310 STEP 20 DLOAD 100 58 SPC 400 TSTEPNL 320 BEGIN BULK NLPARM 110 10 AUTO YES NLPARM 120 10 AUTO YES LOAD 800 0 01 1520 510 LOAD 900 0 05 1 0 510 The rest is same as what in the Bulk Data Deck in the 15t Example ENDDATA Example 3 E
104. R SHEAR 6 67973E 00 3 12898E 01 69 43 7 31044E 02 3 13928E 03 1 20412E 03 3 49256E 00 3 51245E 01 24 50 4 31611E 02 4 39967E 02 4 35789E 02 9 62188E 00 4 12887E 01 87 82 1 50513E 01 2 74268E 03 1 37887E 03 7 95162E 00 7 79520E 01 8 69 7 87298E 02 9 19334E 02 8 53316E 02 9 82619E 00 6 18361E 01 10 43 1 35034E 02 9 17641E 01 1 13399E 02 8 54160E 00 7 97555E 01 21 66 8 20804E 00 5 02440E 02 2 47116E 02 9 62188E 00 4 12887E 01 88 29 7 18274E 01 7 30808E 02 4 01318E 02 7 62246E 00 7 54499E 01 9 93 4 03775E 02 9 14045E 01 2 47590E 02 3 49256E 00 3 51245E 01 1 76 2 79987E 03 7 15284 01 1 43570E 03 4 97689E 00 4 53933E 01 12 53 1 80594E 03 1 44653E 02 8 30642E 02 9 22442E 08 1 90999 08 14 50 3 00425E 03 3 72761E 02 1 31574E 03 3 93396E 16 3 95636E 17 65 65 4 07956E 02 5 57717E 02 4 82836E 02 JULY 29 2004 MSC NASTRAN 7 23 04 PAGE 19 YERED COMPOSITE ELEMENTS FB FAILURE INDEX FOR BONDING MAX OF FP FB FOR ALL ELEMENTS FLAG INTER LAMINAR STRESSES 0 0013 0 0007 0 0019 0 0016 0 0020 0 0017 0 0019 0 0015 0 0007 0 0010 REFERENCED BY GLOBAL PLY 0 0055 0 0019 0 0020 0 0019 0 0015 0 0012 CHAPTER 4 87 Elements 4 3 GPFORCE and ESE Output for DMIG and GENEL The effects of the GENEL element and user supplied DMIG matrices in linear statics solution sequence SOL 101 are now included in the Grid Point Force summations The GPFORCE output includes individu
105. RES1 Boundary pressure for port 1 Real gt 0 0 Required if NPORT 1 or 2 1 PRES2 THETA2 NPNT OFFSET1 OFFSET2 Remarks CHAPTER 7 153 Rotor Dynamics Angular position for port 1 See Remark 2 0 0 lt Real gt 360 0 Required if NPORT 1 or 2 Boundary pressure for port 2 Real gt 0 0 Required if NPORT 2 Angular position for port 2 See Remark 2 0 0 lt Real lt 360 0 Required if NPORT 2 Number of finite difference points for damper arc Odd integer lt 201 Default 101 Offset in the SFD direction 1 Real Default 0 0 Offset in the SFD direction 2 Real Default 0 0 1 The XY YZ and ZX planes are relative to the displacement coordinates of GA and GB The plane coordinates correspond to the NLRSFD directions 1 and 2 GA and GB should be coincident grids with parallel displacement coordinate systems Wrong answers will be produced if this rule is not followed 2 The angular measurement is counterclockwise from the displacement x axis for the XY plane the y axis for the YZ plane and the z axis for the ZX plane OFFSET1 Damper housing ID center offset displacement relative to OD center in the horizontal direction Entered as a positive value for horizontally to the left negative x direction displacement OFFSET2 Damper housing ID center offset displacement relative to OD center in the vertical direction Entered as a positive value for downward negative
106. RM LTLEND or FORM lt ostype gt The FORM BIGENDIAN FORM LITTLEENDIAN FORM LTLEND and FORM lt ostype gt specifications used when the generated output file is to be processed on a platform other than current platform The format appropriate for the platform on which the file is to be processed the target platform must be specified FORM LTLEND is equivalent to FORM LITTLEENDIAN The FORM lt ostype gt specification can by used as a convenience allowing the desired output format to be specified using the target platform OS name or vendor if there can be no ambiguity instead of its actual binary file format lt ostype gt can be one of the following AIX FUJITSU HPUX IRIX PRIMEPOWER SOLARIS SUPERUX or UXPV These are equivalent to BIGENDIAN ALPHA LINUX or WINDOWS These are equivalent to LITTLEENDIAN 235 236 12 13 14 15 16 17 See the MSC Nastran 2004 r3 Installation and Operations Guide for further information on binary file formats For all platforms except Cray UNICOS the FORM describer is ignored for the DBLOAD INPUTT2 and INPUTT4 modules MSC Nastran determines the actual file format when it accesses the specified file If the FORM describer is specified on an ASSIGN statement for these logical keys the syntax of the describer will be validated but will otherwise be ignored Note however that the DBLOAD and INPUTT2 modules cannot process input files in other than the native bin
107. SC Software corporate logo and Simulating Reality are trademarks or registered trademarks of the MSC Software Corporation in the United States and or other countries NASTRAN is a registered trademark of NASA PAMCRASH is a trademark or registered trademark of ESI Group SAMCEF is a trademark or registered trademark of Samtech SA LS DYNA is a trademark or registered trademark of Livermore Software Technology Corporation ANSYS is a registered trademark of SAS IP Inc a wholly owned subsidiary of ANSYS Inc ABAQUS is a registered trademark of ABAQUS Inc All other brand names product names or trademarks belong to their respective owners NA V2005 Z Z Z DC REL Table of Contents Preface 1 MSC Nastran 2005 Release Guide 2 Nonlinear Analysis CONTENTS MSC Nastran 2005 Release Guide m List of MSC Nastran Books x m Technical Support xi m Internet Resources xiii m Release Guide Introduction 2 Nonlinear 2 Numeric Enhancements 2 Elements 3 Dynamics 3 Optimization 3 Rotor Dynamics 4 DDAM 4 Further Enhancements 4 m MSC Nastran Explicit Nonlinear SOL 700 Beta Capability 6 Introduction 6 a Linear and Nonlinear Analysis 7 a Description of the SOL 700 Executive Control Statement 8 Executive Control Parameters 9 m MSC Nastran Implicit Nonlinear SOL 600 33 Additions to the SOL 600 Executive Control Statement 33 Temperature Dependent Stress Strain Curves 37
108. Type can be one of the following DISP VELO or ACCE data describes the units that the motion is described in Data can be one of the following G acceleration data in Gs F Displacement Velocity or Acceleration data in feet ft sec or ft sec I displacement velocity or acceleration in inches in sec or in sec or M displacement velocity or acceleration in meters m sec or m sec CHAPTER 8 191 DDAM Processor dir describes how many spectra are in the file dir can be 1 a single spectrum will be used for all three shock directions or 3 there are three spectra in this file one for each direction freq describes the units for the frequency terms Choices are RAD radians or HERTZ frequency in hertz interp describes the axis plot type Data can be any one of the following LOGLOG both axes are logarithmic LINLIN neither axis is logarithmic LOGLIN the frequency axis is logarithmic the other is not or LINLOG the frequency range is linear the other is logarithmic The BEGIN DATA entry precedes each frequency motion data section If dir 1 there will be only one BEGIN DATA entry if dir 3 there will be three one preceding each section The data section is ended with the END FILE entry This is included to remove the machine specific vagaries of reading to the end of a file FILES CONTENTS AND ENTRY NAMES ARE CASE SENSITIVE USE CAPITAL LETTERS Sample user spectrum data file sampl
109. X2 are collected by examining X2 of all POINT entries involved Segment Thickness input T or T id for PNAME field of DVPREL1 This is available only for CP and OP New PBRSECT PBMSECT and POINT entries are generated after each design cycle 98 The stress recovery points C D E and F are automatically selected by internal logic that will pick POINTS with extreme coordinates that is closest to the four corners of the rectangle defined by the overall width and height that encloses the cross section If a POINT is on a section defined as a design variable in a design optimization analysis then the POINT will move as the design variable changes However the location of the POINT itself cannot be defined as a design variable Example Z Section Beam 2 0 4 0 2 0 Figure 4 2 Z Section Uniform Thickness of 0 1 The required bulk data entries to define the above section for linear analysis is as follows 1 2 3 4 5 6 7 8 9 10 POINT 1 0 0 0 0 POINT 2 2 0 0 0 POINT 3 2 0 3 9 POINT 4 3 9 3 9 POINT 5 3 9 4 0 POINT 6 1 9 4 0 POINT 7 1 9 0 1 CHAPTER 4 Elements 1 2 3 4 5 6 7 8 9 10 POINT 8 0 0 0 1 SET3 SID DES ID1 ID2 ID3 SET3 10 POINT 1 THRU 8 where DES description can be POINT GRID or ELEMENT PBRSECT PID MID FORM PBRSECT 1 1 GS OUTP 10 wher
110. Young s modulus Real gt 1 0 default 3 0 2 0 lt POWER lt 4 0 is suggested PID Property entry identifier Integer gt 0 Remarks 1 The topologically designable element property includes PROD PBAR PBARL PBEND PBEAM PBEAML PSHELL PSHEAR PSOLID and PWELD Multiple TOPVARs are allowed to design different element types in a single file 2 All designed element properties must refer to a entry therefore a PCOMP cannot be used in topology optimization 3 If DELXV is bank the default is taken from the specification of DELX parameter on the DOPTPRM entry New Responses Compliance and Fractional Mass The existing DRESP1 entry has been extended to provide two new response types that are available exclusively for topology optimization The format for the new responses is shown in Table 6 4 and it is seen that both new response types require only the specification of the response type and no other attributes Table 6 4 New Responses for Topology Optimization Response Attributes Response Type RTYPE ATTA ATTB Integer gt 0 or Integer gt 0 Real gt 0 0 ATTI Integer gt 0 COMP Remark 1 BLANK BLANK BLANK BLANK BLANK BLANK Remark 1 2 138 Remarks 1 RTYPE COMP compliance of structures p u and FRMASS mass fraction of designed elements entries are used for topology optimization only 2 RTYPE FRMASS is the mass divided by the mass calculated if all design variables are 1 0 FRMASS i
111. al GENEL element identifications and DMIG matrix names Element strain energy for GENEL elements and DMIG matrices is also calculated The existing Case Control commands ESE for element strain energy and GPFORCE for Grid Point Force are used to request the output Below is a sample F06 output illustrating the inclusion of the DMIG contribution to the grid point force summation GE T POINT Fo OE BALANCE POINT ID ELEMENT ID SOURCE Tl T2 pai R1 R2 R3 11 F OF SPC 3 128563E 06 9 800248 05 1 989233E 01 4 673181 03 5 798827 03 8 957655 01 11 K11X 3 128563 06 9 800248 05 1 989233 01 4 673181 03 5 798827 03 8 957655 01 11 TOTALS 0 0 2 328306E 10 1 421085 13 3 637979 12 7 275958 12 0 0 12 12 QUAD4 2 193838 06 1 597768 05 1 398442 01 1 416497 03 9 718338 03 1 905801E 00 12 K11X 2 193838 06 1 597768 05 1 398442 01 1 416497 03 9 718338 03 1 905801 00 12 TOTALS 9 313226E 10 4 074536E 10 2 772893 12 7 776180 11 3 037712 10 6 550316 14 13 12 QUAD4 9 914453E 05 3 166309 05 5 283162 00 6 762946 02 6 893261 03 6 008299 01 13 13 QUAD4 9 914453E 05 3 166309 05 5 283162 00 6 762946 02 6 893261 03 6 008299 01 13 TOTALS 3 143214E 09 5 820766E 11 2 898037E 11 3 363994 10 1 509761 10 3 552714 14 14 13 QUAD4 1 665495 06 1 313788 06 2 721329 401 1 409337 03 4 590343 03 2 426860 01 14 14 QUAD4 1 665495 06 1 313788 06 2 721329 01 1
112. al file the most common option and s to use an externally defined shock spectrum not based on coefficients These inputs are not case sensitive The format for the external coefficient file is described in Format of Coefficient File on page 185 and the user spectrum format is described in User defined Shock Spectra on page 190 The external coefficient file also contains provision for a modal mass cutoff percentage and a minimum value If either c or is chosen another prompt will appear asking for the name of the external file Are you using DDS 072 or NRL 1396 style equations CR use DDS 072 equations n use NRL 1396 equations DDS 072 and NRL 1396 differ slightly in the format of the equations and how many coefficients are required for different scenarios This choice allows you to use either format ENTER THE DESIRED NASTRAN INPUT FILE NAME Default CR ddam f11 This is the f11 file output by the MSC Nastran run It is necessary to type in the full file name If the program is unable to find or open the file a secondary prompt will inform you of that and prompt for a new name After successfully specifying the name the program will echo the filename that it opened and the unit number associated with it 164 ENTER THE DESIRED VERIFICATION OUTPUT FILE NAME LH Default CR dl ver This file
113. an Any string or value listed on the SOL 700 ID statement is also valid as an environmental variable If the environmental variables are placed in the system wide rc file they may be used by a company for all MSC Nastran users and even hide the fact that dytran Isdyna is being spawned if so desired The following describes the various options for PATH We suggest the use of PATH 3 for Linux and UNIX and path 1 for Windows 1 be used with Windows and Linux only If PATH 1 is specified MSC Nastran will determine the proper command to execute a serial dytran lsdyna run To aid MSC Nastran in determining where dytran lsdyna is located the dynrun pth file must be located in the same directory where the 10 MSC Nastran input file resides The dynrun pth file must contain one line providing the location complete path of the dytran ls dyna run script A typical example of the line in the file dynrun pth follows Windows c sol700 Linux msc users sol700 A string is appended to this path to form the complete command used to execute dytran lsdyna dytran lsdyna jid name dytr dat O name dytr d3hsp G name dytr d3plot D name dytr d3dump F name dytr d3thdt A name dytr runrsf B name dytr d3drfl For Windows MSC Nastran will spawn dytrna Isdyna using the following command assuming the MSC Nastran input data is named enf2e dat Although the example appears as if it is on multiple lines it is actually on a single line
114. an 2005 introduces new capabilities and enhancements to existing capabilities while improving solution accuracy and performance This guide covers all new functionality that has been added to the MSC Nastran program since the MSC Nastran 2004 r1 release in September 2003 and includes 2004 r2 2004 r3 and 2005 r1 In addition some of the new capabilities discussed in this guide are initial implementations considered to be in beta form and offered for trial purposes Nonlinear The horizons of MSC Nastran continue to broaden as development pushes the program forward to take on more advanced and complex types of analysis The release of MSC Nastran 2004 brought a new dimension to the analysis capabilities of MSC Nastran with a new implicit nonlinear solution sequence SOL 600 that embodies MSC Marc taking the product into the realm of complex highly nonlinear calculations with contact and advanced materials The trend continues this year with the preliminary release of the explicit nonlinear solution sequence SOL 700 comprising MSC Dytran and LS Dyna to the MSC Nastran family of solvers This new capability offered in beta form with MSC Nastran 2005 allows complex explicit nonlinear calculations including crash and impact analysis in this initial phase of implementation Also many known issues have been addressed concerning implicit nonlinear SOL 600 increasing overall robustness of the solution sequence Also available in MSC Nastran 2
115. an be stretched to a few thousand design variables By contrast BIGDOT has demonstrated the ability to solve problems with tens of thousands of design variables with the maximum size approaching one million variables A reference for the BIGDOT algorithm is Vanderplaats G Very Large Scale Optimization presented at the 8th AIAA USAF NASA ISSMO Symposium at Multidisciplinary Analysis and Optimization Long Beach CA September 6 8 2000 The BIGDOT algorithm is available in MSC Nastran 2005 and is offered as an additional option as a royalty product that is outside the MasterKey concept Potential users of this capability should contact their MSC sales representative to get information about the Topology Optimization option within MSC Nastran The Guidelines and Limitations section of this subchapter discusses how this new option interacts with the standard Design Optimization option Benefits The primary benefit of including the BIGDOT option is that it enables the ability to perform topology optimization of real world structures As Topology Optimization Beta Capability on page 135 indicates topology optimization entails creating a design variable for each individual element so that one can very quickly exceed to the several thousand design variable practical limitation that is mentioned above for the DOT algorithm A second benefit that will be of interest to some clients is that it can be applied in sizing applications where the n
116. and optimization calculations for DFREQ and with multiple boundary conditions Theory The multiple boundary conditions for ANALYSIS MFREQ or DFREQ in SOL 200 are implemented with the addition of a boundary condition loop in the DMAP level Each pass of the new DMAP loop for a boundary condition has identical theoretical background Input Output The MBC for and DFREO in SOL 200 is implemented with no new user interface requirement An input file can be prepared by merging several previous SOL 200 DFREQ or for the same structures that have different boundary conditions or simply adding DSO related entries to a SOL 108 or 111 file that has multiple boundary conditions Examples TPL mbc01 dat mbc02 dat mbc03 dat All three test files have analysis type of MFREQ Portions of mbc01 will be utilized for this discussion The subcase structure of mbc01 is shown SUBCASE 1 ANALYSIS LABEL SPC Force SPC 100 DESSUB 1 FREQUENCY 501 SUBCASE 2 DESOBJ MIN 1 ANALYSIS MFREQ LABEL SPC Force SPC 200 FREQUENCY 502 CHAPTER 6 129 Optimization Note that the response for design objective is selected from the second subcase while responses for design constraints are from SUBCASE 1 This arrangement is only for demonstration purposes DESOBJ with a global response such as WEIGHT can appear either above the SUBCASE level or in the first SUBCASE The ou
117. and solution sequences to run in MSC Nastran 2005 The format of the following modules has been modified in MSC Nastran 2005 such that the MSC Nastran 2004 format is not upwardly compatible with MSC Nastran 2005 and or their behavior is not upwardly compatible The changes are described in the next section BDRYINFO DOPR3 DPD ELTPRT FA1 FRLG GUST MODQSET MPP NLCOMB NLTRLG SDRHT TRLG WEIGHT The following is a list of existing modules with new features or fixes which require format changes in MSC Nastran 2005 but are not documented here because their MSC Nastran 2004 formats are considered upwardly compatible in MSC Nastran 2005 They are fully documented in the MSC Nastran 2005 DMAP Programmer s Guide BCDR DISOPT DOM11 DOM12 DOM6 DOM9 DOPFS DOPR1 DSAD DSAL DSAW DSPRM DSTAP2 FA2 GKAM GP1 GP4 GPFDR GPSP IFP9 INPUTT2 MAKAEFS MATMOD MKRBVEC MODGM2 MPYAD NLITER NLSOLV OUTPRT SDRCOMP SEPIX SEQP SMPYAD SSG1 1 The following is list of new modules in MSC Nastran 2005 They not documented here but are documented in the MSC Nastran 2005 DMAP Programmer s Guide DSGRDM GDC GUSTLDW ILMP1 ILMP2 ILMPGPF MDENZO MODCASE NDINTERP SLITX DMAP Module Changes This section shows the changes for DMAP module instructions which were changed from MSC Nastran 2004 to 2005 The module change descriptions are presented as differences with respect to the MSC Nastran 2005 DMAP Programmer s Guide which is available on t
118. are printed for each vector These values can be used to determine if the model is over constrained contains constrained DOF not connected to the SUPORT point In general Epsilon terms should be less than 10 Strain energy is a measure of elastic energy in the model resisting rigid body motion Theoretically it should be zero for DDAM but in practice it usually has some small value As a rule 1 is acceptable for translations and 100 is acceptable for rotations If strain energies in the range of 10 or greater are encountered this is an indication that a constrained degree of freedom not connected to the SUPORT entry probably exists in the model such as an unintentionally grounded CELAS Keep in mind however that these values are all model dependent If the strain energies are non zero for the first three SUPORT points which correspond to the translational directions it is an indication of non singular degrees of freedom that are constrained While MSC Nastran allows this to take place it violates the assumptions made in this DDAM processor resulting in incorrect modal masses and participation factors in that direction As a result the final NRL results will be incorrect To comply with the MSC Nastran DDAM assumptions it is necessary to connect all non singular degrees of freedom that are to be constrained to the SUPORT point What this means is that the only SPC entries in the model should be for singular rotational DOF SPC entri
119. area are reserved in the dictionary and stored in the DAT array The DAT array is copied to both the control area and the primary map block for file management The logical file number assigned by the OPENC is returned to the calling application program Subroutine Name OPENR 1 Entry Point OPENR 2 Purpose Open existing keyed objects for random access updating and return logical file reference 3 Calling Sequence CALL OPENR DBNUM NAME WRDREC FILNUM KEYLEN D2 D3 D4 D5 D6 IRET 4 CHAPTER 9 Miscellaneous retrieve its DAT control area DBNUM Integer input Logical database number Dicti NAME ictionary entry and object name to update WRDREC Integer output Number of words per record in object Logical handl h FILNUM Inicgercouig t ogica andle number assigned to the object KEYLEN Integer output The number of words in the key 0 gt Used Hierarchal Method n Used B Tree Method D2 D3 Currently unused In prior releases D4 Integer input these arguments represented memory D5 addresses for I O buffer work areas D6 IRET Integer output Return code from the routine 0 gt Normal data block open 1 Requested NAME does not exist 2 gt Too many logical files open 3 gt Currently unused In prior releases it indicated too few buffers allocated 4 gt Object already open Method DICRDR is used to check the existence of the object NAME and to
120. ark 4 Character AUTO TSTEP ADAPT or SEMI Default AUTO KSTEP The criteria for the stiffness matrix update See Remark 5 Integer gt 0 Default 2 Remarks 4 The stiffness update strategy as well as the direct time integration method is selected in the METHOD field If the AUTO option is selected the program automatically selects the most efficient strategy to update matrix adjust the incremental time step and use bisection If the TSTEP option is selected the program updates the stiffness matrix every KSTEP increments of time step The bisection will be applied only when the convergence cannot be reach by updating matrix and no automatic time step adjustment If the ADAPT option is selected the program automatically adjusts the incremental time step and bisection This method only updates matrix at every KSTEP convergent bisection solutions If the SEMI option is selected the program will update the stiffness matrix after the first iteration at each time step and then assume the normal AUTO option The stiffness matrix is always updated for a new STEP or Restart irrespective of the option selected 5 For AUTO and SEMI options the stiffness matrix is updated on convergence if KSTEP is less than the number of iterations that were required for convergence with the current stiffness For ADAPT option stiffness is updated every KSTEP converged bisection solutions For TSTEP stiffness is updated at e
121. ary format That is a binary file in BIGENDIAN format cannot be processed on a LITTLEENDIAN platform and vice versa For MSC Nastran on Cray UNICOS the FORM describer is required for the DBLOAD INPUTT2 and INPUTT4 modules if the file does not have the default format For the DBUNLOAD and OUTPUT2 modules if FORM is other than UNFORMATTED or equivalent e g BIGENDIAN on an AIX or HPUX platform and LITTLEENDIAN on a Linux or Windows platform then only data blocks with an NDDL description are processed See the MSC Nastran 2005 DMAP Programmer s Guide under the DATABLK statement An NDDL description is required for TYPE TABLE and none is required for TYPE MATRIX The data block must be processed with FORM UNFORMATTED if TYPE UNSTRUCTURED KDICT or KELM See the MSC Nastran 2004 r3 Installation and Operations Guide for further information on sys spec controls and on machine dependent aspects of the ASSIGN statement Also if there are SYS specifications on more than one ASSIGN statement specifying the same log name or logical key UNIT combination the second and subsequent specifications will appended to the current SYS specification with a comma separator Currently the RECL keyword is used by the DBC module and has a default minimum of 1024 words The maximum allowed is 65536 words and is used to increase the database capacity The SIZE keyword is used by the DBC module and has a default of 16777215 The maximum allowed is 2147483647 a
122. ase control commands which can be placed below the subcase level can also placed below the step level For example all steps in above examples use the same Case Control command NLPARM 100 in SUBCASE 1 and TSTEPNL 200 in SUBCASE 2 The SOL 400 uses an enhanced dynamic solution algorithm which makes the linear static solution and the nonlinear static solution become special cases of the general nonlinear solution procedure For this release only the linear static analysis and the nonlinear static analysis can be mixed in one SUBCASE For example SUBCASE 10 STEP 1 ANALYSIS LNSTATIC LOAD 10 STEP 2 ANALYSIS NLSTATIC LOAD 20 NLPARM 20 In above example SUBCASE 10 has two steps the first step requests a linear static analysis and the second step requests a nonlinear static analysis The default ANALYSIS method i e there is no ANALYSIS command in the Case Control file is NLSTATIC CHAPTER 2 47 Nonlinear Analysis Vector Operations and Convergence Criteria The convergence criteria are specified by using the Bulk Data entry TSTEPNL in the nonlinear transient analysis In performing the convergence tests we compute three error factors the displacement the load and the work energy error factors which are printed in the Nonlinear Iteration Summary Table These three error factors must satisfy the error tolerance rules specified by CONV EPSU EPSP and EPSW on the Bulk Date entry TSTEPNL In comput
123. ase 3 temp load 13 LOAD 300 38 BEGIN BULK param mrafflow mymatO0 param mrtablsi1 4 param mrtabls2 1 NLPARM 2 10 PARAM LGDISP 1 tempd 10 70 tempd 11 110 tempd 12 700 tempd 13 1100 SLOAD 20 1 0 2 0 1 loud LOO lx x3 road 200 2 lead 300 I l l X PLOAD4 1 1 Constraint Set 1 Unt SPC 1 1 SPC 1 8 SPC 1 15 SPC 1 22 SPC 1 29 Property 1 Untitled PSHELL 1 1 Material 1 AISI 434 1 TABLE 35000 MAT 1 2 9E 7 MT 1 215000 240000 MAT4 14 861E 4 T 2 3 2345678 2345678 2345678 MATTEP 1 1 1 TABLEM1 7 70 0 6 6E 6 2000 6 2 6 52345678 2345678 2345678 5 21 70 0 31 2000 35 TABLES1 31 r 0 150002 0 160 99999 40000 END TABLES1 32 po 03 130090 0 140 TABLES1 33 100 11009 0 12 0 TABLES1 34 k Qu 9000 Oty LO n 99999 24000 END TABLES1 35 gt 5000 LOG 70 299999 15000 ENDI GRID 1 0 r 99999 28000 ENDI 99999 25000 ENDI AUTO 1 itled 123456 123456 123456 123456 123456 gt 0 125 d 0 Steel 2 CAUCHY ISOTROP ADDMEAN 0 327 331E 4 156000 38 647 331E 4 4 5 6 20 1 0 6 6E 6 05 7 8 9 2345678 2345678 2345678 2345678 2345678 2345678 21 6 4 6 1500 6 3E 6 2345678 2345678 2345678 2345678 2345678 2345678 000 6 5E 6 200 ENDT 000 32 200 E
124. ating a design variable that modifies the constraints so that 8 5 j 1 2 ncon and the transforms the objective function so that D PENAL oj where PENAL is the user defined penalty parameter is the initial objective function and p is initialized to the maximum initial constraint value If this maximum value is less than CTMIN the transformation is not applied In this way the maximum constraint value is never positive while the penalty on the objective acts to force the D value to zero If there is a feasible design this technique should lead to it If there is not this will result in a compromise design where the maximum constraint violation is minimized CHAPTER 6 123 Optimization Input The only user input is the PENAL parameter that can be input on the DOPTPRM entry A suggested value for this parameter is 2 0 with larger values serving to move the design more forcefully toward the feasible design space Experience to date shows that a value of 2 0 works well Outputs This transformation is only applied during the approximate optimization and is therefore not evident in standard reporting of the optimization results i e the results produced with DOPTPRM parameters P1 and P2 sensitivity prints and the summary DESIGN HISTORY information The prints produced when DOPTPRM IPRINT is used to display the approximate optimization results do include this transformation so the user must be
125. ation purposes Note that the W in the equations represents the weight not mass in 1000s of pounds kips Also note that the equations deliver the accelerations in Gs and the velocity in in sec These conventions are hard coded into the ddam f program Mode 1 AA AB M4 50 40 11 368 o 7 Mi AC 11368410 1208 VA VB Mi 120 50 11 368 V ee M Ve ag Spe N E 344 6 in sec Vio _ Tom _ 344 6 89 72 _ A e Baga gt Since is less than Ay use A for the calculation Mode 2 AA AB 50 40 11 368 AT yee 6 VA VB Mi 120 50 11 368 Wc Mu EXC M VC 11368410 Vao 2 Vo 344 6 89 72 _ ES C ie 12 This time A is larger than so we use A for the calculations here Step 7 Use the Accelerations Eigenvectors Individual Weights and Participation Factors to Find the Dynamic Forces on the Masses The weights are the individual weights not masses or modal masses F 182 W X11P A 8000 0873 5 423 80 0 302 994 Ib e Fy W5X21P A 6000 2329 5 423 80 0 606 248 Ib Mode 2 Fiy W X12P A 5 8000 2017 2 610 169 711 743 Ib Foy 6000 1008 2 610 169 266 771 Ib Step 8 Use the Mass Forces to Get the Forces in the Springs Mode 1 Spring 1 303 0 606 2 909 200 Ib Spring 2 606 2 606 200 Ib Mode 2 Spring 1 711 7 266 8 444 900 Ib S
126. ber of SUBCASE commands and no STEP command in a Case Control file SYSTEM 401 Selects the convergence parameter computation method and the divergence solution checking method to simulate the SOL 129 If ITRFMT 1 use method similar to SOL 129 TZEROMAX SYSTEM 373 Controls initial time step adjustment in nonlinear transient analysis File Management Statements The following File Management statements are required for restarts Please refer to the File Management Statements in Chapter 2 of the MSC Nastran Quick Reference Guide or Chapter 12 of the MSC Nastran Reference Manual for details ASSIGN Assigns physical file names to database files that are used by a Nastran data file to run a job RESTART Requests that data stored in a previous run be used in the current run Executive Control Statement SOL 400 or SOL NONLIN Requests the SOL 400 general nonlinear solution sequence Parameters PARAM LANGLE Selects the method to represent large rotations in a geometric nonlinear analysis 1 for the Gimbals angle method 2 for the left rotation method and 3 for the right rotation method The default value is 3 for the nonlinear transient analysis PARAM LGDISP Requests a geometric nonlinear analysis PARAM FOLLOWK Requests whether the follower force stiffness will be used in a geometric nonlinear analysis PARMA FKSYMFAC Controls whether the symmetrical follower force
127. bitrary Beam Section capability Benefits The new user interface for describing cross section shapes of CBAR and CBEAM element types will provide users with the ability to More easily model 1 D structural components with arbitrary cross sectional profiles using the MSC Nastran BAR and or BEAM element types for analysis in linear solution sequences Design an optimal cross section profile in the Design Optimization solution sequence SOL 200 to optimize the overall model performance This new capability the Arbitrary Beam Section will be delivered in the MSC Nastran 2005 r2 but is available for beta testing in MSC Nastran 2005 r1 Inputs and Outputs Essentially the shape of the beam cross section is defined using sets of POINTS as defined on the SET1 or new SET3 Bulk Data entry subsequent development phases will allow section definition using geometric entities GMCURV These sets are then referenced by new Bulk Data entries PBRSECT for the BAR PBMSECT for the BEAM CHAPTER 4 97 Elements used to define the cross section form parameters and reference material properties The types of section that can be defined include a General Section Open Profile and Closed Profile with various parameters required on the PBRSECT or PBMSECT entries to define outer perimeter inner perimeter and branch segments where applicable Currently for the BEAM element only a constant cross section beam is supported Once all of the b
128. ble with more efficient data storage and access However different types of machines have different formats and so transferring data from one format to another involves a process of transmitting from the remote machine to a neutral format copying the neutral format results data over to the local workstation and receiving to the local workstation to rebuild a compatible binary file Such a process is cumbersome and requires large amounts of disk space and can lead to reduced accuracy through loss of precision Benefits MSC Nastran has been enhanced to allow the user to specify the format in which binary OP2 OP4 OUTPUT2 and OUTPUT4 files are generated regardless of the computer platform on which MSC Nastran is running note that this new capability will not be available on Cray UNICOS Therefore a user running MSC Nastran on a platform such as Linux i386 the source machine can request that a generated OP2 4 file be suitable for a platform such as IBM AIX or Hewlett Packard HP UX the target machine This allows the OP2 4 file to be used by post processing programs running on the target machine directly without having to go through a TRANS RECEIVE data transfer process This increases ease of use reduces disk requirements and overall processing time The target machine specification is entered through new options for the FORM qualifier on the OUTPUT2 and OUTPUTA ASSIGN statements in the File Management Section of the input
129. bulk data The benefits for OUTPUTA files are even greater MSC Nastran on all platforms except Cray UNICOS will be able to read binary OUTPUTA files from any platform except Cray UNICOS directly and without the need for any intermediate translation Also for users who read OUTPUTA files into their own programs a translation program will be available that will allow binary OUTPUTA files to be copied and transformed from one format to another 204 Theory The term Endian refers to the byte ordering for numeric data used by a particular computer architecture Big Endian specifies that the most significant byte MSB of a data element is stored at the lowest byte address while Little Endian specifies that the least significant byte LSB of a data element is stored at the lowest byte address Most UNIX platforms i e almost all except Compaq Alpha are big endian machines while all Intel x86 and compatible platforms e g Intel Pentium and AMD Athlon including those running both Windows and Linux are little endian machines Some machines like Intel Itanium can be run in either big endian mode e g when running HP UX or in little endian mode e g when running Linux or Windows Inputs and Outputs OUTPUT2 OUTPUT4 and INPUTT4 modules have been modified to allow the user to specify the format of a binary file generated by these modules i e whether the file is to be in big endian format or little en
130. bution in nonlinear transient response TMPSET Defines a time dependent dynamic thermal load group for use in TTEMP Bulk Data entry Examples The following three examples show the inputs of the nonlinear transient analysis The intention of these examples is to show the input structure for SOL 400 The model itself and the detailed entries in the Bulk Data file are not important Example 1 Example EX01 is simplified from the standard QA file NLTSUBO2 This model only has QUAD4 elements It has both material nonlinearity MATS1 and geometrical nonlinearity PARAM LGDISP 1 The 18 STEP will process the output data at every 5 output time steps and the 2 d STEP do it only once because of the settings of the parameter NLPACK All the bold font statements are entries pertaining to the nonlinear analysis ITLE ISOTROPIC MATERIAL amp 51 UBTITLE SPC CHANGE IN EACH STEP ID MSC 01 5 150 SOL 400 CEND T S E SET 10 10000 11200 SET 20 101 SEALL ALL DISPL ALL STRESS 20 SUBCASE 100 S S ANALYSIS NLTRAN TEP 10 PARAM NLPACK 5 DLOAD 100 SPC 200 TSTEPNL 310 TEP 20 NLPACK 1 DLOAD 100 SPC 400 TSTEPNL 320 ELLIPTIC CYLIND NLPACK s ER UNDER 01 BEGIN BULK PARAM NDMAP 0 0 PARAM LGDISP 1 STEPNL 310 100 0 01
131. by NO on TSTEPNL Bulk Data entry which is also the last time step of each output package controlled by NLPACK parameter CHAPTER 2 51 Nonlinear Analysis The geometry and the initial material properties of the structural model cannot be modified This is obvious because any modification to the geometry or the initial material properties would invalidate the previous analysis and require the nonlinear solution to start from the very beginning In such cases it is simpler to initiate another cold start The procedure to perform the restart for the nonlinear transient analysis is similar to the nonlinear static analysis in SOL 400 therefore no further discussion here Temperature Excitation A new capability which has never been supported in the original nonlinear transient analysis SOL 129 is added into SOL 400 when ANALYSIS NLTRAN It is the time dependent dynamic thermal effect which is applied to all the nonlinear elements in the residual The time dependent thermal elastic equation can be written as follows a T t T t To Trep where 1 the thermal strain T t thecurrent temperature is defined in T t T is the temperature field and f t is the time function T ef the reference temperature the stress free temperature initial temperature and T the coefficient of thermal expansion To all nonlinear elements the temperature effect in bo
132. cks allocated to the database See Remark 16 Remarks 1 The ASSIGN statement and its applications are discussed further in the Database Concepts on page 513 of the MSC Nastran Reference Guide 2 Thelog name or logical key describer must be the first describer on the ASSIGN statement All other describers may appear in any order With the exception of log name logical key filenamel filename2 sys spec describers and values longer than four characters may be abbreviated to four characters 3 For FORTRAN files the logical key names and their default attributes are listed in Table 2 1 If a logical key name is identified as Assignable YES then the defaults may be overridden on the ASSIGN statement 234 b Iffilenamel is omitted or is specified as or Certainreserved names may not be used for log names or logical key names These names are the logical names listed in Table 2 1 that are identified as Assignable NO This list includes SEMTRN LNKSWH MESHEL LOGFL INPUT PRINT INCLD1 and CNTFL If they are used then a fatal message is issued Also unit numbers 1 through 10 14 16 18 19 and 21 should not be assigned PUNCH and PLOT may be used but are not recommended If one of the logical key names indicated in the Remarks 3 and 4 is not specified on this statement then it is assumed to be a DBset member name log name as shown in Format 1 Ifthe same log name is used on more than one DBse
133. complished by making a complete copy of the original MSC Nastran input file and spawning off a new job with the SOL statement changed and an INCUDE statement for the DMIG file 34 MSC Nastran will switch to SOL 107 to compute complex eigenvalues MSC Marc will generate OUTPUT4 matrices for friction stiffness and possibly damping on a file specified by pram marcfil2 name and time specified by param marcstif time This is accomplished by making a complete copy of the original MSC Nastran input file and spawning off a new job with the SOL statement changed and an INCLUDE statement for the DMIG file MSC Nastran will switch to SOL 111 to compute modal frequency response MSC Marc will generate natural frequencies and mode shapes that are read into MSC Nastran from a file specified by param marcfil3 name Same as option 3 except that SOL 112 for linear transient response will be used MSC Nastran will switch to the solution sequence given in field 9 of the MDMIOUT entry In addition the DMIG entries specified by MDMIOUT will be included in a separate MSC Nastran execution spawned from the original execution Case Control and Bulk Data will be added to the original input to properly handle these matrices in the spawned MSC Nastran execution CHAPTER 2 35 Nonlinear Analysis An example of input using the continue 1 option is as follows SOL 600 106 path 1 stop 1 continue 1 TIME 10000 CEND param marcbug 0 ECHO sort DISP print
134. cription of the DRESP1 entry The input requirements for the new CSTRAT response type are very similar to those for the existing CFAILURE response type Outputs Representative output produced for the CSTRAT response based on the P2 parameter is shown in Figure 6 1 while Figure 6 2 shows representative formatted sensitivity output for this response RESPONSES IN DESIGN MODEL N A BOUND NOT ACTIVE OR AVAILABLE IUNCICTOLUACE ANALYSIS SUECAS ES 1 OE COMPOSITE LAMINA STRESS RATIO RESPONSES Picard INTERNAL DRESP1 RESPONSE ELEMENT COMPONENT LAMINA LOWER UPPER LABEL NO BOUND VALUE BOUND 1 3 FISUM 101 5 1 N A 2 2166E 01 N A 2 333 CFAILXX 101 5 2 1 0000 00 2 2166 01 Figure 6 1 Display of the CSTRAT Response Values CHAPTER 6 Optimization 115 5 DESIGN SENS TIILTVTITX MATRIX OU TP Ut i RESPONSE DENS WOILCTOX DRESP1 ID 2 RESPONSE TYPE CSTRAT ELEM ID 101 COMP NO SEID 0 SUBCASE RESP VALUE LAMINA NO DESIGN VARIABLE COEFFICIENT 1 2 2166E 01 1 1 ORIENT 1 7345E 02 DRESP1 ID 333 RESPONSE TYPE CSTRAT ELEM ID 101 COMP NO SEID 0 SUBCASE RESP VALUE LAMINA NO DESIGN VARIABLE COEFFICIENT 1 2 2166 01 2 1 ORIENT 1 7285 03 Figure 6 2 Formatted Sensitivity Output for the CSTRAT Response Guidelines and Limitations
135. cture is found by increasing the number of elements The ideas of making a finer finite element mesh is to get a better finite element solution However this finer meshing tends to have an increasing number of members with decreasing size This more detailed topology solution creates a problem from a manufacturing point of view An overview of the techniques used to avoid the checkerboarding and mesh dependent solutions can be found in the reference 1 In SOL 200 filtering algorithms are used to promote a checkerboard free and mesh independent topology optimized solution Topology otimization is powerful tool to generate design concepts in the early design stage Unfortunately the topology optimzed designs usually turn out to be infeasible for certain manfacturing processes such as casting and extrusion This issue will be addressed in a future MSC Nastran release 144 Example 1 topex1 dat This example leads to a conceptual design of a bicycle frame in a 2D situation by maximizing the stiffness for a given amount of material 70 mass reduction that shown in Figure 6 7 satisfies two boundary condition and load cases mmy Figure 6 7 Bicycle Frame Two loading and constraint conditions are assumed corresponding to two scenarios riding the bicycle on sitting and standing positions as shown in the figures below There are 2442 QUADA elements and 2 TRIA3 elements CHAPTER 6 145 Optimization Figure 6 8 FE Model of a
136. cy ranges and thousand of modes it may become very time consuming A new technique for calculating frequency response quantities is activated by the Bulk Data parameter PARAM FASTFR When PARAM FASTFR YES is specified the alternative technique is used For large models with thousands of modes and a judicious use of structural damping speedup compared to the conventional FRRD1 module is of the order 10 to 1 CHAPTER 4 Elements Temperature Dependent Composites Support Extended to Unsymmetric Laminates B Global Ply Results Tracking E GPFORCE and ESE Output for DMIG and GENEL Bar Element Torsional Mass Moment of Inertia PARAM COUPMASS Lumped Mass Option E QUADR Convergence Behavior Arbitrary Beam Cross Section Pre Release 4 1 Temperature Dependent Composites Support Extended to Unsymmetric Laminates In MSC Nastran 2004 laminated composites analysis was extended to include temperature dependent ply materials in SOL 106 Nonlinear Analysis This approach is based on updating the smeared laminate properties of symmetric laminates for the nonlinear QUAD4 and TRIA3 elements The temperature dependency of the ply materials was extended to include both orthotropic and anisotropic materials Furthermore the more accurate integral strain method was added to complement the default secant thermal strain method The symmetric laminate limitation in SOL 106 is now removed and membrane bending coupling effects due
137. d nproc are omitted the default is 1 For parallel execution the directory where the MSC Nastran input file exists must be shared with read write privileges If wdir is used it must also be shared see below The directory where the dytran lsdyna executable resides must also be shared for parallel execution In addition all rules for MPICH must be followed properly see your system administrator to be sure all computers are properly configured for parallel execution using The version of MPICH to use is 1 2 5 as of the initial SOL 700 release It can be obtained from ftp mcs anl gov if necessary bat Run in background or forground default debug Output many messages from the script or batch file memory Amount of memory Example memory 20m steps Number of steps 1 or 2 default is 2 Two steps means that lsdyna is executed twice once to form the structured input file and again to analyze it Although steps 1 is faster there are some models that fail using the steps 2 option wdir Working directory For parallel execution this directory must be shared with read write privileges Default is directory where MSC Nastran input resides copy Yes or no Input and output files are copied from wdir to the input directory Default is yes delete Yes or no LS Dyna scratch files are deleted or not Default is yes 12 machine Machines and number of processors to use in the form machinel 2 machine2 4 use 2 processors
138. dentification number of a Case Control command SET definition The members of the specified SET represent the identification numbers of the finite elements that are to be retained in the reduced 2 file element connection data block OGRDSET Integer Default 0 Identification number of a Case Control command SET definition The members of the specified SET represent the identification numbers of the grid points that are to be retained in the reduced 2 file grid geometry data block OPCHSET Integer Default 0 SET punch request flag If OPCHSET 1 then the list of grid points used to reduce the grid point geometry data block will be punched in Case Control SET definition format OMSGLVL Integer Default 0 Set consistency check error message severity flag The default causes FATAL messages to be generated if the grid set is not consistent with the element related grid point set and the job is terminated If OMSGLVL 1 the FATAL messages are reduced to WARNINGS and the job is allowed to continue OGRDOPT Integer Default 1 Selects the method used to create the set of grid points retained in the reduced grid point geometry data block The default simply uses the set of grid point IDs listed in the OGRDSET Case Control SET Set consistency is checked OGRDOPT 2 uses the list of grid point IDs that are connected to elements in the OELMSET Case Control SET OGRDOPT 3 merges the contents of the OGRDSET Case Control SET with the
139. dian format The ASSIGN statement is used to assign physical files used by MSC Nastran to FORTRAN units and the desired output format is specified using the FORM option For FORTRAN files the format of the ASSIGN statement is ASSIGN logical key filename UNIT u STATUS NEW OLD UNKNOWN FORM FORMATTED UNFORMATTED BIGENDIAN LITTLEENDIAN LTEND ostype DEFER TEMP DELZERO DELETE SYS sys spec In addition for OUTPUTA files a new utility program OP4UTIL has been developed that can test and convert OUTPUTA files from one endian format to another The OPAUTIL utility may be used to validate copy or reformat binary files created using the MSC Nastran OUTPUT4 module The basic format of the op4util command is Msc2004 op4util options file names These capabilities are available on all platforms except Cray Unicos Examples To specify the endian format the ASSIGN statement is used as follows Set the default OP2 file format to BIGENDIAN and assign two OP2 files one to unit 12 with filename test op2 12 and one to unit 35 with filename test op2 35 in ASCII mode ASSIGN OP2 BIGENDIAN ASSIGN OP2 test op2 12 UNIT 12 CHAPTER 9 205 Miscellaneous ASSIGN OP2 2 test op2 35 UNIT 35 FORM FORMATTED The OPAUTIL program is used as follows To generate a usage help message msc2004 op4util msc2004 op4util h elp msc2004 op4util To convert a file from one big endian to litt
140. dulus and density penalty factor p is introduced to enforce the design variable to be close to a 0 1 solution when gt 1 0 The penalty factor p usually takes values between 2 and 4 The general topology optimization problem available in MSC Nastran can be stated as follows Minimize f x D Subject to gj x lt 0 0 j 1 M lt x lt 10 1 2 N where g represents the j th constraints and M is the total number of constraints The constraint specification can be general in that any of the response types currently available in SOL 200 can be used N is the total number of designable elements isa small positive number to prevent the stiffness matrix singularity 136 Benefits Topology optimization can generate more efficient design concepts in the early design stage especially for load paths Topology optimization can also be to used to obtain rib patterns and weld distribution patterns The BIGDOT optimizer is available to solve problems with a large number of design variables and constraints that DOT struggles with due to computer memory requirements and efficiency Input Topology optimization in MSC Nastran borrows heavily from the user interface developed for sizing and shape optimization In particular the design objective and constraints are defined in an identical manner for topology and sizing shape optimization This section discusses the additional bulk data entry that has been provided to ease the c
141. e FORM can be GS General Section OP Open Profile CP Closed Profile PBMSECT PID MID FORM PBMSECT 2 1 GS OUTP 10 PBMSECT 2 defines a constant section beam The z section example showing the OP option with thickness definition is as follows 1 2 3 4 5 6 7 8 9 10 POINT 11 0 0 0 05 POINT 12 1 95 0 05 POINT 13 1 95 3 95 POINT 14 3 9 3 95 SET3 20 POINT 11 THRU 14 PBRSECT 1 1 OP OUTP 20 T 0 1 T 2 0 1 PT 12 13 12 1 OP OUTP 20 T 0 1 99 100 Further examples are available in the Test Problem Library zbr3 dat zbr4 dat zbr5 dat zbm3 dat zbm4 dat zbm5 dat CHAPTER 5 Dynamic Analysis C Set Improvements E Enhancements to the MODESELECT Case Control Command E Automatic Q Set AUTOOSET B Enhancements to Dynamic Excitation Processing in DPD Module E Enhancements to Transient Response Analysis kal 5 1 C Set Improvements When performing modal synthesis with free or mixed boundary conditions the c set mass is usually included in the calculation of the component modes A new parameter ZROCMAS has been introduced to allow the c set masses to be set to zero when computing component modes For the case where the component has large masses on the c set degrees of freedom or when the user requests too many modes for the component the c s
142. e enhanced QUADR element and improvements in accuracy carry over to areas of the model that are more coarsely meshed Existing QUADA element models can easily be converted to QUADR elements by setting a single System Cell QRMETH in the NASTRAN Statement Inputs System cell ORMETH 5 will convert all QUAD4 TRIA3 elements the model to QUADR TRIAR Example To demonstrate the difference in accuracy between the QUADR and QUADA elements various mesh densities for a simple T Section test model were run using MSC Nastran 2004 r3 comparing von Mises stress results taken in the central position at Element 6 as shown CHAPTER 4 93 Elements Four analysis runs were made using for element edge lengths 0 1 0 05 0 025 and 0 0125 to vary the number of elements increasing the mesh density E The four element stress contour plots below show a very similar stress distribution for all four mesh densities however the actual stress values do vary slightly between the plots 94 The results for each of the four MSC Nastran runs were tabulated and plotted to compare the QUAD4 and QUADR elements CHAPTER 4 Elements Quadr Quad4 Comparison 450000 400000 350000 300000 250000 200000 Von Mises Stress 100000 50000 0 150000 0 0 02 0 04 0 06 0 08 0 1 Mesh Density 0 12 It is evident that the MSC Nastran QUA
143. e minimum response FUNC MATCH indicates that the DRESP2 specifies a matching task as shown in the Theory section above The METHOD attribute can be either LS indicating that the least squares method is to be utilized while METHOD BETA indicates that the minimization of the maximum normalized difference is to be performed For METHOD BETA the C coefficients can be input again with defaults of 100 005 and 10 0 120 Outputs There are no added outputs produced by this enhancements with the exception that the spawned design variable that is produced for FUNC BETA or for FUNC MATCH with METHOD BETA will appear in the prints of design data The ID for the spawned design variable is the maximum number for the existing DESVAR plus 1 Similarly spawned responses will appear as normal responses The ID for the spawned DRESP2 starts from 100 000 001 and the response label is pre defined as B BETA for FUNC BETA and as LOW BETA or UPP BETA for FUNC MATCH with METHOD BETA Guidelines and Limitations The new FUNC options on the DRESP2 can only be used on DRESP2 s that are invoked by the DESOBJ entry For FUNC BETA only DRESPI data be provided For FUNC MATCH DTABLE data provides the target points for each of the responses that is specified using a DRESP1 These data must be provided in matching pairs A target value of 0 0 is not recommended with FUNC MATCH Other constraints can be used in combination with the objective func
144. e spectrum file 2 4 5 6 DATATYP ACCE I 1 2 LOGLIN acceleration vs frequency file acceleration in in sec 2 BEGIN DATA dee Bees 1055 100 1000 point added to define range 500 800 1000 500 END FILE kd 8 8 MSC Patran Interface Starting in Version 2004 MSC Patran has an analysis option that enables you to set up and run a DDAM analysis The MSC Patran interface will create the control file write the file assignments and allow entry of the SUPORT card Any type of DDAM analysis can be run from within MSC Patran including the coefficient runs and user input spectrum runs The program performs several checks on the data that is entered to prevent the user from accidentally entering bad data and then trying to run the model Program Operation Choosing the Solution Type from the main analysis menu will bring up the following form MEC Solution Type Solution Type LINEAR STATE HONLINEAR STATIC NORMAL MODES BUCHLING COMPLEX EIGEN ALLE f FREQUENCY RESPONSE TRANSIENT RESPONSE TRANSIENT PLEIT 7 DDAM Solution Select lt Solution Parameters Solon Sequence 187 ow CHAPTER 8 193 DDAM Processor The Solution Parameters button brings up the following form On the Subcase parameters form most of the rest of the DDAM input is
145. ear transient analysis integration scheme using dytran lsdyna It may also be used for implicit static analyses using LS Dyna s Dynamic Relaxation or slow buildup options The calculations will not be performed directly within MSC Nastran Instead SOL 700 will use a separate solver based on LS Dyna which is spawned from MSC Nastran This client server approach is similar to SOL 600 using MSC Marc For linear analyses such as normal modes frequency response or linear direct transient response MSC Nastran should be used For the first phase of this project the SOL 700 statement will spawn dytran lsdyna which uses an MSC Dytran text input interface to LS Dyna dytran lsdyna is a 3D explicit nonlinear analyses code with DMP parallel processing domain decomposition capabilities For Phase 2 of the project and beyond fluid coupling airbags seat belts and dummy passengers will be added Then the user will be able to select the standard MSC Dytran program or an enhanced dytran Isdyna program Inputs and outputs will be the same as or similar to the familiar MSC Nastran inputs and outputs or at the user s request LS Dyna type outputs will be available The LS Dyna style outputs are the default for SOL 700 CHAPTER 2 9 Nonlinear Analysis For ID 129 or NLTRAN SOL 700 will generate a dytran lsdyna input data file jid dytran dat where jid is the name of the MSC Nastran input file without the extension For example if the MSC Na
146. ecessary to run the entire analysis or perform that portion of the analysis on a separate computer The DDAM package as implemented in MSC Nastran performs the analysis in three phases as outlined in the following steps 1 SOL 187 is used to perform a fixed base modal analysis Additionally it calculates modal participation factors and modal effective mass 2 Running the DDAM program which accepts ASCII OUTPUTA data from MSC Nastran performs shock excitation calculations using the user supplied shock coefficients and generates shock spectrum data Additionally it terminates the shock excitation calculations when a specified modal mass is reached Options are provided in this step to use equations based upon the modal masses of each mode or a user input design spectrum to compute the shock excitations This will be run automatically from within MSC Nastran using the ISHELL capability unless directed otherwise 3 Continuation of the MSC Nastran Sequence using output from part 2 to perform DDAM motion and stress recovery following the NRL modal summation convention Data is calculated and output for MSC Patran post processing This will automatically follow step 2 in SOL 187 MSC Patran Interface on page 192 describes the MSC Patran interface that automates the process including coefficient and file selection The following section describes the process in detail with notes and documentation for all of the parameters and data required
147. ed function by first finding bounds and then using polynomial interpolation 8 Find the minimum of a constrained function by polynomial interpolation extrapolation without first finding bounds on the solution Remarks 1 If ADSCOD gt 0 ADSCOD will override the METHOD 2 A more complete description of the available options can be found in the Reference cited in the introduction of this section 134 Output The outputs used with the ADS code are identical in terms of format to those using the DOT code with the exception of the prints produced using the DOPTPRM IPRINT parameter The IPRINT output from ADS will differ for each option but all IPRINT results are headed by a banner the identifies the results as coming from the MSC Software enhanced version of ADS Guidelines and Limitations The ADS code has been provided in response to client requests for an alternative optimization algorithm to the DOT code MSC Software has performed extensive testing of using ADS on our suite of over 400 test problems The basic conclusion from these tests is that the ADS code performs adequately on many of these tests but that there is no compelling case to recommend the use of ADS on a general basis It is recommended that knowledgeable users apply ADS to some of their difficult optimization tasks and see if they can obtain improved results In particular ADS SUMT methods can comfortably solve problems with a few thousand design var
148. ed in this release to compute the true value of H based on the two hardening slopes H and H it passed Simply to say we must find H based on the Eq 2 1 and the following two equations H de Hyde Hyde Eq 2 2 and de de de Eq 2 3 where de is the total plastic strain increment in one sub increment and de and de are the plastic strain increments corresponding to hardening slope and H An iterative method has been added to MSC Nastran when computing Eq 2 1 Eq 2 2 and Eq 2 3 to obtain the best or say converged H Note that even though MSC Nastran 2005 can handle multiple hardening slope case in Plasticity itis still not recommended to loading too fast in nonlinear analyses That because if a sub increment crossing three or more hardening slopes the converged H may be very hard to obtain Example The following example shows the difference between Theoretical results MSC Nastran 2004 results and MSC Nastran 2005 results ID PLASTICITY SOL 400 DIAG 8 CEND NLPAR 400 SET 1 12 23 34 SET 2 2 11 22 31 DISPL eu STEP 1 LOAD 100 STEP 2 LOAD 200 STEP 3 LOAD 300 STEP 4 LOAD 400 STEP 5 LOAD 500 STEP 6 LOAD 600 STEP 7 LOAD 700 STEP 100 BEGIN BULK GRID 11 Oy On 123456 GRID T2 9 TO 13456 CROD 1 101 11 12 PROD 101 100 dus 1 100 7 MATS1 100 101 PLASTIC 100 TABLES1 101 T T Dey 0 deh 100 25 2 732995 lt EH U 4 5 370 ENDT STABLES1
149. eful doing this The theoretical outline in Theoretical Background on page 172 can serve as a guide The methods should be tested on a small model to assure that all the appropriate masses coefficients etc are CHAPTER 8 171 DDAM Processor modified Also note that the NRL sum must be either performed manually external to MSC Nastran or the DMAP altered to accommodate combining results from the symmetric and anti symmetric runs References 1 R O Belsheim and G J O Hara Shock Design of Shipboard Equipment Part I Dynamic Design Analysis Method NAVSHIPS 250 423 30 May 1962 2 Shock Design Criteria for Surface Ships Naval Sea Systems Command NAVSEA 0908 LP 000 3010 Revision 1 September 1995 3 M M Hurwitz A revision of the Dynamic Design Analysis Method DDAM in NASTRAN Naval Sea Systems Command December 1982 4 NAVSEA Design Data Sheet DDS 072 Confidential 5 Scavuzzo amp Pusey Naval Shock Analysis and Design Shock and Vibration Information and Analysis Center SAVIAC 2000 Reference 1 outlines the original concept of DDAM as applied to Naval Shipboard equipment Reference 2 is the NAVSEA specification latest version that gives specifics for performing this type of analysis Reference 3 describes the procedure for using DDAM within the framework of modern finite element codes Reference 4 contains the classified NAVSEA coefficients for calculating the spectral quantities in the response eq
150. ement 75 76 F F06 output file 161 226 feasible design 122 File Management Statements ASSIGN 53 159 RESTART 53 fluid modes 103 flutter analysis 199 fractional mass 137 G GDACMS 130 GENEL 87 global ply IDs 83 GPFORCE 87 I Implicit Nonlinear SOL 600 33 initial condition 110 ISHELL 158 L large field input 214 Little Endian 204 LS Dyna 6 lumped mass 89 M matrix diagonal 77 MAXRATIO 77 MDACMS 130 128 modal effective mass 103 modal frequency response 78 125 modal mass 170 modal masses 180 MPYAD 215 MSC Access 218 MSC ADAMS 197 MSC ADAMS modal neutral file 198 MSC Marc 36 MSC Patran 192 multiple boundary conditions 128 multiple hardening slopes 67 INDEX 257 N NLRSFD 150 Nonlinear Iteration Summary Table 48 52 NRL summation 177 O OP2 206 OP4UTIL 204 OUTPUT2 159 203 227 OUTPUT4 158 203 P parallel processing 39 participation factors 179 PBUSHT 41 PCOMPG 83 PKNLS 199 PKS 199 ply results tracking 83 PUNCH 214 Q QUADR 92 R reduced 2 file 206 residual vectors 125 Restart 50 results recovery 226 S shock coefficients 180 shock spectra 190 shock spectrum 162 SMPYAD 215 SOL 129 47 SOL 187 158 258 INDEX SOL 200 125 130 131 201 SOL 700 8 SOL 400 43 Bulk Data Entries NLRESTART 50 BCTABLE 17 23 NLSTAT 43 CBUTT 19 23 NLTRAN 43 CCRSFIL 19
151. erence to and TMPSET 2 4 CHAPTER 2 67 Nonlinear Analysis Correction in the Solution Algorithm for Elasto Plastic Material The solution algorithm for Elasto Plastic material in nonlinear analyses works best for single hardening slope in MSC Nastran 2004 and earlier versions When there are multiple hardening slopes which defined on the TABLES1 Bulk Data entry as stress strain curve MSC Nastran may produce some numerical error after loading procedure processes into the 2nd and higher hardening slopes This numerical error is derived from the calculation of the scalar multiplier a Lagrange multiplier da any D l de E E Eq 2 1 Zn where the gradient vector 9f 96 is computed by differentiating the stress function f 6 representing effective stress D is the elasticity matrix de is the strain increment and H is the slope of hardening In Plasticity analysis when a sub increment along the stress strain curve crossing two hardening slopes for example H and H the old solution algorithm will picks up one of them depending on the estimate stress increment to be the value of H H is always equal to either H or H however none of them can represent the true hardening slope in this condition that s how the numerical error building up In other word the true value of H must be the function of both H and H when it goes through two hardening slopes A new iterative algorithm is add
152. es should not be used for other reasons such as symmetry constraints or non moving foundation points Calculation of Shock Spectrum ddamish ddamish exe on NT is an interactive batch program that performs shock spectrum calculation for the structure under consideration Structural data consisting of natural frequencies and participation factors that were generated by MSC Nastran are utilized here as input data The program queries the analyst for spectrum inputs loading characterization and other details In general this program is run in batch mode by MSC Nastran with the answers supplied by the ddd control file CHAPTER 8 163 DDAM Processor The following discusses the various prompts in the program if it is run interactively Do you coefficients CR use default coefficients 5 have a shock spectrum or are you using use other coefficient file user input shock spectrum The program has a provision to include a set of shock coefficients compiled into the code Hitting CR will use these coefficients The default coefficients provide capability to cover the full range of Navy coefficients in DDS 072 including surface and submerged ships deck hull and shell mount elastic and plastic The user has the option to input custom coefficients for any or all of the configurations selectively Note that the choices are CR carriage return for yes c for coefficients stored in an extern
153. ese profiles to be optimized in SOL 200 Improvements to the QUADR element are evident with improved convergence behavior particularly for coarsely meshed models You can now obtain grid point force output for DMIG and GENEL type definitions Dynamics Improvements to the dynamic analysis capabilities of MSC Nastran include The support of multiple boundary conditions for frequency response analysis in SOL 200 Better handling of c set masses during the calculation of component modes Enhancements to dynamic excitation processing Enforced motion calculations In addition the MODESELECT Case Control command has been extended to include easier mode selection for all selection criteria essentially replacing many of the existing mode selection bulk data parameters as well as adding a new criteria based on modal effective mass Optimization As well as the new nonlinear solution sequences MSC Nastran 2005 offers a beta topology optimization capability This addition to the existing SOL 200 optimization solution sequence allows optimization analyses to be performed that require many design variables a typical requirement of topology optimization Other optimization enhancements include New functions for DRESP2 3 4 A new response type for DRESP1 The ability to transform an approximate optimization task to a feasible design ncreased accuracy with dynamic response optimization analyses through the use of res
154. et residual flexibility will become singular causing the component reduction to fail Setting the parameter ZROCMAS to YES will avoid this condition by excluding the c set masses when calculating the component modes 5 2 CHAPTER 5 103 Dynamic Analysis Enhancements to the MODESELECT Case Control Command The MODESELECT Case Control command which was first made available in MSC Nastran 2004 has been greatly enhanced with the addition of several new options The enhanced command permits the user to specify ALL data related to mode selection without the need for any parameters The command which can be employed for selecting either structure modes or fluid modes offers five different and distinct options The details and usage of the enhanced command are clearly described in the MSC Nastran Quick Reference Guide A short description of the various options available with this command is listed below 1 Mode selection based on arbitrary mode numbers This option is the same as the one and only one that was available in MSC Nastran 2004 2 Mode selection based on the number of lowest modes This option is similar to the usage of the LMODES LMODESFL parameter 3 Mode selection based on range of mode numbers This option can be regarded as a variation of options 1 and 2 above 4 Mode selection based on frequency range This option is similar to the usage of the LFREQ LFREQFL and HFREO HFREQFL parameters However this opt
155. f Inertia p Density L Element of Length I and J Area Moments of Inertia For COUPMASS 1 the axial mass will be consistent rather than coupled An example test file can be found in the TPL brbm dat 4 5 CHAPTER 4 89 Elements PARAM COUPMASS Lumped Mass Option The MSC Nastran Quick Reference Guide documentation for PARAM COUPMASS suggests that its default value of 1 causes the generation of lumped mass matrices that contain only translational components for the elements listed therein Notable exceptions to this are the CBAR and CBEAM elements both of which will yield rotational and coupling terms in order to preserve the mass center when element offsets are defined This offset mass is lumped in the sense that it has low matrix rank and is coupled in the sense that there are non zero off diagonal terms in the mass matrix The CBEAM element will also yield a mass moment of inertia about the local X axis of the element and if system cell 39850 then this is also true of the CBAR element In order to yield a lumped mass matrix containing translational components only for the CBAR and CBEAM elements system cell 414 has been introduced The default value of this system cell 0 leaves the current behavior unchanged whereas a positive integer value for system cell 414 along with the default value for PARAM COUPMASS 1 will yield lumped mass matrices containing only translational components for both CBAR and CBE
156. factors deck coefficients COEF SURF DECK ELPL 625 50 1 0 225 50 1 50 10 2 0 505 6 hull coefficients COEF SURF HULL ELPL 30 60 120 25 50 1 0 5z T0 40 10 45 5 6 5 15g shell coefficients COEF SURF SHELL ELPL 25 50 1 0 25 50 1 0 LO 45 5 6 5 15 It is important that all fields be 8 characters or spaces long as there is a bug in the read routine that should have been fixed for MSC Nastran 2005 that requires this This is easily achieved by padding the ends of lines with blanks to achieve the full 8 character length CHAPTER 8 187 DDAM Processor Control File Format The control file is simply a list of responses to the questions that the DDAM Fortran program asks The format can be any one of three depending on which user options are being requested No special user options FET nsurf nstruc nplast pref amin f a_axis vert_axis 11 filename 13 filename ver filename User coefficient option coef dat filename nsurf nstruc nplast pref amin f a axis vert axis 11 filename 13 filename ver filename User spectrum Option E TI spec dat filename pref amin f a_axis vert_axis 11 filename 13 filename ver filename Specific file formats as follows First Line spectrum control format a1 1x a1 1x a1 First item DDAM or general spectrum run flag T General non DDAM spectrum run F DDAM Second item
157. formed TOT ITER Total number iterations performed including the number of stiffness updates Restart The purpose of a nonlinear restart is to allow the user to use the material or the geometrical properties of a previously converged solution as a new starting point to continue the analysis This is useful when the user want to change the loading sequence the solution criteria or to extend the analysis For SOL 400 a user friendly restart procedure has been implemented For the nonlinear transient analysis only the following principles are listed in this release note The restart must be continued at previous converged solution point in a nonlinear transient analysis by specifying a SUBCASE STEP and or TIME This is accomplished by using the Case Control command NLRESTART please refer to Case Control Commands in Chapter 4 of the MSC Nastran Quick Reference Guide When a job has ANALYSIS NLSTAT in SOL 400 it can restart at any user specified load steps controlled by NOUT in NLPARM Bulk Data entry The tremendous size of database should be required when ANALYSIS NLTRAN in SOL 400 if the same logic mention above is used To reduce the size of database and save the CPU time of I O a new parameter NLPACK is introduced in nonlinear transient analysis in SOL 400 please also see Outputs on page 52 e for the details of this new parameter The nonlinear transient job can only restart at the closest output time step controlled
158. generated 12 modes 1 2 3 4 5 6 8 9 define the matrix as 12 row 3 column matrix MI PARTNVEC 0 2 1 12 3 define col 1 keep all modes 1 12 f a shock MI PARTNVEC 1 1 THRU 12 define col 2 keep modes 1 2 and 3 athw shock M PARTNVEC 2 1 1 2 1 3 1 define col 3 keep only mode 5 vert shock F O Fo MI PARTNVEC 3 5 1 Be sure to ask for all the modal mass 100 in the DDAM program if you use this option since it will perform its own partitioning on the output from the DDAM program Special Circumstances Mode by Mode Output It is occasionally desirable to look at DDAM output on a mode by mode basis Such occasions can be model or methodology verification or to gain a better understanding of which modes are contributing to particular results Mode by Mode output is controlled in MSC Patran by the normal output requests and by three parameters In SOL 187 the parameters are XBYMODE YBYMODE ZBYMODE Because mode by mode output can generate a large volume of data three parameters are included to handle just mode by mode data in specific directions For example PARAM XBYMODE YES Will generate data only for the X direction In addition to the F06 file printed output each parameter generates a separate plot file with all the mode by mode results that have been requested These three files are in units 41 43
159. he MSC Software Combined Documentation 2005 CD ROM The CHAPTER 10 243 Upward Compatibility change descriptions below includes the MSC Nastran 2005 format of the module with changes in bold text Any new or changed data blocks and parameters are also described below the format BDRYINFO The first parameter ASMUNIT is obsolete and has been removed DOPR3 The UNUSED data block has been removed and DIT and DYNAMIC are moved into the 18th and 19th positions Format DOPR3 CASE EDOM DTB ECT EPT DESTAB EDT OL DEQIND DEQATN BGPDT DVPTAB VIEWTB OINT PELSET XINIT FOL DIT DYNAMIC OBJTAB CONTAB R1 TAB RESP12 RSP1CT FRQRSP CASEDS OINTDS PELSETDS DESELM RESP3 ADRDUG ADRDUTB CASADJ MODRSP CASEDM RESP12X RESP3X CONTABX OBJTABX ARVEC DMRESD S N DESGLB S N DESOBJ S RICNT S R2CNT S CNCNT SOLAPP SEID S EIGNFREQ PROTYP DSNOKD SHAPES S N R3CNT RGSENS INREL S N ADJFLG S N TADJCOL AUTOADJ SOLADJC S N NORMEV 5 DPD The amplitude data in DLT has been moved into five new output matrices to support machine precision enforced motion Format DPD DYNAMIC GPL SIL USET UNUSED5 PG PKYG PBYG PMYG YG GPLD SILD USETD TFPOOL DLT PSDL RCROSSL NLFT TRL EED EQDYN APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN LUSET S N LUSETD S NOTFL S NODLT S NOPSDL DATAR
160. he file must be explicitly opened Access If SEQ the file is opened for sequential access If DIRECT the file is opened for direct access sdir The scratch directory specified using the sdirectory keyword data out Notes CHAPTER 9 239 Miscellaneous The name of the input data file with all directory and extensions removed The directory and file prefix specified using the out keyword or taken by default The actual logical key name for this is OP2 If you use OUTPUT even though this is still the logical key name put out by MSC Patran you will get a user fatal message from MSC Nastran FORMATTED is required for neutral format OUTPUT files and ASCII format OUTPUTA files Cray Unicos the default Form is UNFORMATTED For all other platforms the Form is ignored See Remark 12 Example The following example demonstrates the form of the modified ASSIGN and POST entries The expected result would be that files rsltsubc subc1 and rsltsubc sub2 would contain the results for subcase 1 and 2 respectively assign opcase rsltsubc ID MSC RSLTSUBC TIME 5 SOL 101 5 CEND MINUTES TITLE WRIT E RESUL ECHO UNSORT DISPL ALL STRES ALI GPSTR ALI post tocase allcase SUBCASE 1 TITLE GPSTRI1 subtitle LOAD 1 post tocase subcl SUBCASE 2 LOAD 2 ITLE GPSTRI1 subtitle
161. he following commands is acceptable prior to MSC Nastran 2005 Disp all Displ all Displa all Displacement all Displcement all Starting in MSC Nastran 2005 the full spelling is checked Correctly spelled short forms are still acceptable e g disp etc For the above example the first four commands are acceptable The last one due to the misspelled command will cause the job to terminate with the following fatal message USER THE FATAL MESSAGE 601 1 KEYWORD ON THE ABOVE CARD TYPE IS ILLEGAL OR MISSPELLED This change is necessary to alleviate problems caused by the lack of uniqueness for checking only 4 characters for certain commands In versions prior to MSC Nastran 2005 the following 2 commands Elstress all Elstrain all are both treated as element stresses elst Starting in MSC Nastran 2005 the command ELSTRAIN will terminate the job with UFM 601 as elstrain is a non existing command 254 D E X MSC Nastran Release Guide A acceleration load 216 ACMS Geometric Domain 74 Matrix Domain 74 adjoint loads 125 ADS optimizer 131 Application Program Interface API 218 Arbitrary Beam Cross Section 96 ASSIGN 203 ASSIGN File Management statement specification of 231 B beam cross section 96 beam offsets 41 Big Endian 204 BIGDOT optimizer 136 buckling 41 Bulk Data Entries ACCEL 216 ACCEL1 216 DOPTPRM 122 134 13
162. he q set degrees of freedom gt 0 No records are written 1 record to GEOMIW 2 SPOINT record to GEOM2W and QSET1 record to GEOM4W Input integer default 0 Starting q set identification number for QSETREC 2 CHAPTER 10 247 Upward Compatibility MPP MP2S inserted after MPSRP Format MONITOR MPSR MPSER MPP AECTRL UXDAT AEMONPT MPAR MPAER MPEU 152 MPSIR MPSRP MP2S MPSERP UXV INDX MACH Q AECONFIG SYMXY SYMXZ MESH Input Data Block MP2S Table of MONPNT2 responses at trim NLCOMB Format NLCOMB CASECC ESTNL KDICTNL BKDICT ETT PTELEMO PTELEM UNUSED8 PT EQEXIN SLT DLT BGPDT APPLOD DYNAMIC LT ELDATA DLT1 NSKIP LSTEP LINC STATIC LGDISP OSTEP 5 Input Data Blocks APPLOD Matrix of applied load amplitudes DYNAMIC Table of Bulk Data entry images related to dynamics NLTRLG Format NLTRLG CASECC USETD DLT SLT BGPDT SIL CSTM TRL DIT GMD GOD PHDH EST MPT APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN PDT TMLD DLT1 TABS 248 Input Data Blocks APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN SDRHT Format SDRHT Matrix of applied load amplitudes Matrix of enforced motion amplitudes UG OEF1 SLT EST DI CSTM SIL US HOEF1 HOES1 RDEST RECM DLT TABS SIGMA NORADMAT Input Data Blocks APPLOD OESNLH Matrix of applied load amplitudes
163. his is the name of the rc file to be used for the second spawned MSC Nastran run The flow of the run is as follows Create a primary MSC Nastran SOL 600 input file we will name it jid dat for this example Submit MSC Nastran in the standard fashion For this example the following command is used nastran jid rc nast1 rc The nast1 rc file contains items such as scratch yes memory 16mw etc The primary MSC Nastran run creates an MSC Marc input file named jid marc dat The primary MSC Nastran run spawns MSC Marc to perform nonlinear analysis MSC Marc generates the required DMIG matrices for this example The nonlinear MSC Marc analyses completes and generates standard files Control of the process returns to MSC Nastran A new MSC Nastran input file named jid nast dat will be created from the original input file This file will contain the CMETHOD Case Control command and EIGC Bulk Data entry all of the original geometry and additional entries to read the dmig002 file A second MSC Nastran job will be spawned from the primary MC Nastran run using the command nastran jid nast rc nast2 rc The nast2 rc file can be the same as nastl1 rc or can contain different items Usually memory will need to be larger nast2 rc than in nast1 rc The second MSC Nastran run computes the complex eigenvalues and finishes Control of the process returns to the primary MSC Nastran run and it finishes CHAPTER 2 37 Nonlinear
164. hly nonlinear problems SOL 700 is primarily intended for engineers and analysts who have constructed an MSC Nastran finite element model for a purpose other than crash but who wish to use the model for crash This avoids having to read the MSC Nastran model into a GUI translate it to LS Dyna or MSC Dytran and thus risk losing or not properly translating some MSC Nastran input data Once you have completed the LS Dyna portion of the execution standard LS Dyna results files such as d3plot as well as standard MSC Nastran files such as op2 xdb punch and f06 are available for postprocessing The capability will be delivered with the MSC Nastran 2005 12 release SOL 700 contains an internal translator that creates an MSC Dytran file If the original MSC Nastran input file is named jid dat or jid bdf the MSC Dytran file that is created is named jid dytr dat The translator examines and converts Executive Control statements Case Control commands and Bulk Data entries to MSC Dytran CHAPTER 2 7 Nonlinear Analysis The MSC Nastran input can contain as many subcases as desired however only one may be selected for use in any particular SOL 700 analysis This is done using the Case Control commands SKIP ON or OFF to pick the desired subcase Linear and Nonlinear Analysis SOL 700 is a dynamic analysis program that can perform linear transient analyses such as SOL 109 as well as nonlinear transient analyses such as SOL 129 It is also
165. hods Input real no default Flutter velocity divisor to obtain flutter indices CASECC USETD DLT FRL GMD GOD DIT PHDH APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN PPF PSF PDF FOL PHF YPF SOLTYP S N FOURIER S N APP Input Data Blocks APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN Matrix of applied load amplitudes Matrix of equivalent enforced motion load amplitudes due to stiffness effects Matrix of equivalent enforced motion load amplitudes due to viscous damping effects Matrix of equivalent enforced motion load amplitudes due to mass effects Matrix of enforced motion amplitudes 246 GUST Format GUST CASECC DLT FRL DIT QHJL UNUSED6 UNUSED7 ACPT CSTMA PHF APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN PHF1 WJ QHJK PFP S N NOGUST BOV MACH Q 5 Input Data Blocks APPLOD ENFLODK ENFLODB ENFLODM ENFMOTN MODQSET Format MODOSET Parameters OSETREC OSETID Matrix of applied load amplitudes Matrix of equivalent enforced motion load amplitudes due to stiffness effects Matrix of equivalent enforced motion load amplitudes due to viscous damping effects Matrix of equivalent enforced motion load amplitudes due to mass effects Matrix of enforced motion amplitudes GEOMI GEOM2 GEOMA GEOM1W GEOM2W GEOMAW NOQSETT QSETREC QSETID Input integer default 0 Records to use in defining t
166. iables MSC Software would be interested in hearing of any experience along these lines One guideline is that while the DOT code has techniques for dealing with infeasible designs ADS is weak in this area In this case itis recommended that the new PENAL parameter on the DOPTPRM entry be used to transform the optimization task from an infeasible to a feasible one 6 8 CHAPTER 6 135 Optimization Topology Optimization Beta Capability Introduction Unlike sizing and shape optimization topology optimization finds an optimal distribution of material given the package space loads and boundary conditions These methods have grown rapidly in popularity and application in recent years and topology optimization methods have been discussed in a large number of publications An overview of topology optimization can be found in a book by Bendsoe and Sigmund 1 and a review article by Rozvany et al 2 MSC Software has integrated a topology optimization capability into MSC Nastran 2005 that is based on the increasingly popular density approach to topology optimization In the density method Young s modulus E and density p are used as intermediate design variables for each designable finite element The actual design variable x is the normalized density that links Young s modulus E and density p for designable finite elements using the following relationships P Pox E Ep where p and are respectively the fully solid Young s mo
167. idual vectors Rotor Dynamics The rotor dynamics capability introduced in MSC Nastran 2004 has been further enhanced to include the modeling of squeeze film dampers DDAM We have introduced a new dynamic design analysis method DDAM solution sequence SOL 187 Widely used in the ship building industry DDAM is a form of shock spectrum analysis used to determine the dynamic response of a component to shock loading Further Enhancements We have added many other enhancements to MSC Nastran 2005 Some are mentioned in the following list Furthering the integration of MSC Nastran with MSC ADAMS are new capabilities that aid model checkout and the determination of component attachment points The new variable endian capability allows easier transfer of OP2 results data between machines with differing binary file formats New ACCEL Bulk Data entries allow easier specification of acceleration loads across the model A new complex conjugate option for matrix multiplication MPYAD has been added facilitating matrix manipulation SPC and SPCD entries are now stored in machine precision New PKS and PKNLS flutter options in aeroelastic analysis CHAPTER 2 Nonlinear Analysis B MSC Nastran Explicit Nonlinear SOL 700 Beta Capability E MSC Nastran Implicit Nonlinear SOL 600 Pre release of the Nonlinear Transient Analysis in SOL 400 E Correction in the Solution Algorithm for Elasto Plastic Material E Correc
168. ign variable than that of the response in the first ply CHAPTER 6 117 Optimization New FUNC tions for the DRESP2 Entry Introduction The DRESP2 has been extended to provide two new functions that allow for the use of the DRESP2 synthesis capability without invoking a DEQATN The first new FUNC is BETA and it simplifies the input when the design task is to minimize a maximum response value The second FUNC is MATCH and this provides a simplified way to specify a design task where one of the requirements is to match analysis results from MSC Nastran with a set of results that could come for example from a structural test Benefits The task of minimizing the maximum response has been found to be useful in a number of applications but particularly in NVH studies where the technique can be used to minimize the peak response across a frequency range This can bea tricky task to implement and the new BETA function provides a convenient way of specifying this design task Users frequently want to use SOL 200 of MSC Nastran to obtain a better agreement between analysis and test results This can be a tedious process and benefits from formulating the task in a way that may not be obvious to all users The addition of the MATCH function greatly simplifies the input preparation and could result in a better agreement than would be obtained from the user s input Theory Minimizing the maximum response value is a technique that has pr
169. ign variables The optimizer can be either DOT or ADS 2 If the user has acquired the TO option only this enables general topology optimization tasks but does not enable standard shape and sizing optimization The optimizer is BIGDOT 3 If the user has both DO and TO the BIGDOT algorithm can then be applied to topology and shape and sizing optimization tasks with a large number of design variables The optimizer can be BIGDOT or DOT or ADS Example The Example 1 topex1 dat on page 144 Topology Optimization utilizes BIGDOT CHAPTER 7 Rotor Dynamics Squeeze Film Damper Nonlinear Force sl 7 1 Squeeze Film Damper Nonlinear Force Introduction The requirement for high power output from modern gas turbine engines has resulted in highly flexible light weight rotor designs Control of vibration response in these engines is a major design problem The use of rolling element bearings with low inherent damping makes it difficult to reduce vibration amplitudes and dynamic loads transmitted to the rotor supporting structure Squeeze film dampers SFDs are therefore used to provide adequate damping to maintain low amplitude vibration levels and to reduce the dynamic loads transmitted to the bearings and rotor support structures The general SFD model has been sucessfully incorporated into the MSC Nastran time domain analysis and this new capability provides the means to design and analyze SFDs for general rotor orbits
170. ing the error factors SOL 129 used the d set vectors for displacements and forces By using this method the effect of SPC loads and MPC constraints are accounted for only indirectly Also there are difficulties to account for the effect of Lagrange multipliers for the Lagrange rigid elements For these reasons in SOL 400 whenever possible the matrix and vector operations which include the computations of error factors are performed in p set the physical set For MSC Nastran set definition please refer to the Quick Reference Guide section 7 1 Another major modification is the computation of the work error In SOL 129 the work error is based on the multiplication of the residual force and the displacement change During iteration both the residual force and the displacement change are become smaller therefore the convergence rate of this value is proportional to the squire of the convergence rate of the solution Thus it becomes very small near convergence Also it does not have a counter part in the physical world In SOL 400 the total work done to structure model is computed during iterations and the work error is estimated based on the total work In this way the work error gives an estimation of error in actual work done to the structural model The total work for each iteration is printed on the Nonlinear Iteration Summary Table Please note that this total work is only an approximation Solution Algorithm and Simulation of SOL 1
171. ing to replace the current nonlinear static solution sequence SOL 106 and the nonlinear transient solution sequence SOL 129 In addition the nonlinear heat transfer solution sequence SOL 153 and SOL 159 will also be included in SOL 400 in the future Up until now SOL 400 does not replace SOL 106 and 129 Benefits The new benefits of SOL 400 are discussed this section Some of the benefits may be subject to the limitation discussed in next section The benefits are The Case Control command STEP which was first introduced in MSC Nastran 2004 to allow user to input a flexible loading and solution sequence at an independent loading SUBCASE in the nonlinear static run is also supported by nonlinear transient analysis User can specify different type of ANALYSIS such as NLSTAT and NLTRAN at different SUBCASE s in a single run The different STEP s can specify different types of ANALYSIS only when they belong to the same kind of analyses such as static or transient analysis For example both NLSTAT and LNSTAT are static analyses therefore they can be mixed in a SUBCASE However NLSTAT and NLTRAN cannot be mixed in a SUBCASE An improved nonlinear iteration procedure to make solution easier and faster to converge All AUTO TSTEP or ITER ADAPT and SEMI which is the method for controlling stiffness updates are supported in the nonlinear transient analysis 44 AUTOSPC be executed when every time updating the matrice
172. ion is more general since it also allows for the UNCONDITIONAL inclusion or exclusion of selected modes regardless of their frequencies 5 Mode selection based on modal effective mass fraction MEFFMFRA criteria This powerful option is the highlight of the enhancement It allows the user to select modes based on different MEFFMFRA criteria Further like Option 4 above it also allows for the UNCONDITIONAL inclusion or exclusion of selected modes regardless of their MEFFMFRA values There are several example problems included in the Test Problem Library that illustrate the use of MODESELECT For SOL 111 kmfmodea b c d s dat For SOL 112 kmtmodea b c d s dat 104 id msc kmtmoded dat SID TEST MODESELECT 5 TEST PROBLEM KMTMODED 5 SOL 112 TIME 30 CEND TITLE TEST PROBLEM KMTMODED MODESELECT IN MODAL TRAN RESP ANALYSIS SUBTITLE TEST OF MODESELECT WITH THE MODAL EFF MASS FRACTION OPTION 5 MODESELECT TIFR T2FR 0 9 T3FR 0 8 MODALSE SORT1 PRINT ESORT ASCEND THRESH 0 0 FREQ ALL all MODALKE SORT2 PRINT ESORT DESCEND THRESH 0 0 FREQ ALL all SUBCASE 1 disp plot all TSTEP 100 DLOAD 10 METHOD 10 BEGIN BULK DYNAMIC LOADING 5 freql 5 1 1 20 Lloggz 20 105 4 teed 9 0 100 0 1040 tstep 100 200 005 20 DAREA 10 13 3 1 EIGRL 10 1000 5 BASIC MODEL DEFINITION GRDSET 777776 GRID T 4 7 40 0 0 123456 GRID 3 4 744 0 9 0 Sp 275742297
173. ions and is thus capable of modeling general damper orbits with broad frequency content The model computes the oil film forces by numerical integration of the instantaneous film pressure distribution Squeeze Film Damper Input Data Format The squeeze film damper SFD is implemented as a nonlinear force similar to the NLRGAP The SFD forces are activated from the Case Control Section using the NONLINEAR command NONLINEAR n The Bulk Data entry for the SFD has the following form 1 2 3 4 5 6 7 8 9 10 NLRSFD SID GA GB PLANE BDIA BLEN BCLR SOLN VISCO NPORT PRES1 THETA1 PRES2 THETA2 NPNT OFFSET1 OFFSET2 Field Contents SID Nonlinear load set identification number Integer gt 0 Required GA Inner e g damper journal grid for squeeze film damper Integer gt 0 Required GB Outer e g housing grid for squeeze film damper Integer gt 0 Required PLANE Radial gap orientation plane XY XZ or ZX See Remark 1 Character Default XY BDIA Inner journal diameter Real gt 0 0 Required BLEN Damper length Real gt 0 0 Required BCLR Damper radial clearance Real gt 0 0 Required SOLN Solution option LONG or SHORT bearing Character Default LONG VISCO Lubricant viscosity Real gt 0 0 Required PVAPCO Lubricant vapor pressure Real gt 0 0 Required NPORT Number of lubrication ports 1 or 2 Integer no default P
174. is ASCII and the format is detailed in Control File Format on page 187 This is the file assigned to unit 21 described above Output Output from SOL 187 consists of the following A small ASCII file as defined by the ASSIGN statement for input to the Fortran program This file contains a list of frequencies participation factors the total mass and the available modal mass in each direction Another small ASCII file also defined in the ASSIGN statement for input back into MSC Nastran from the Fortran program A verification file containing frequencies modal masses participation factors and calculated accelerations The F06 file A OP2 file containing mode shapes Three op2 files containing the NRL summed results The MSC Nastran F06 output file will contain echoes of several matrices constructed in the DDAM process including equation numbers refer to the numbers in Theoretical Background on page 172 OMEGX the vector of natural frequencies rad 162 PAB The participation factor matrix P defined in equation 9 MTOT the six diagonal terms of MTOTC MEFF the six diagonal terms of MEFFC MFRACT the ratio of effective to total mass for each direction PAB MTOT and are output to unit 11 by an OUTPUT4 module for use in Part 2 In addition when the program calculates the rigid body vectors about the SUPORT point values of Epsilon and Strain Energy
175. is the intermediate result echo This file contains the summary of modes modal mass and mass percentages for each shock direction The default name is the name of the f11 file you specified but with a ver extension This file is useful to verify which modes are contributing most to a model s response ENTER THE DESIRED NASTRAN OUTPUT FILE NAME I Default CR d1 f13 This is the file that will be used as input for the MSC Nastran restart in Part 3 The default name is constructed similarly to the verification default but with f13 appended to it Wha r3 Whe H D Wha p cf 3 type o te te ty te ship do we have or SURFACE default coefficients For SUBMERGED default coefficients Fh Fh T FY he equipment mounted For DECK default coefficients default coefficients ELL default coefficients H ey ky 0 WN EF ct rn 9 da Ci H m factors do you want ELASTIC default coefficients EL PL default coefficients Hosp These three questions choose the appropriate shock coefficients The notation default coefficients after the description indicates that the coefficients for that configuration were read from the list built into the program If the user has specified some or
176. ition line are important as are the capitalization The first line must be in the FORTRAN format a1 1x a1 1x a1 with the T or F capitalized The axis line is the same format but with X Y or Z for each term A sample file for a conventional analysis might look like T 1 i Pai d1 f11 d2 f11 dl ver S 8 7 User defined Shock Spectra This section describes the program package that allows for defining a user input shock spectrum Not to be confused with the user input shock coefficients this routine allows the user to completely define the spectrum as data pairs of frequency and some motion quantity displacement velocity or acceleration The user can define the spectrum in selected units as outlined in the following section The frequency scale and or the disp vel accel scale can be either logarithmic or linear as frequency and value ranges often cover several orders of magnitude The data is entered into a user created file which can have any arbitrary name In general the file is fairly simple comments anywhere in file DATATYP type datal dir freq interp BEGIN DATA data fo data data BEGIN DATA data datas data BEGIN DATA f data f2 data data The data on the DATATYP entry are as follows type describes what motion quantity is described in the following data
177. l File Format 187 m User defined Shock Spectra 190 MSC Patran Interface 192 Program Operation 192 m MSC Nastran ADAMS Integration 198 Overview 198 Limitations 198 Alternative Solution Algorithms for Flutter Analysis 199 Introduction 199 Benefits 200 Input 200 Guidelines and Limitations 201 Example pkswep dat 202 m Little Big Endian 203 Variable Endian OUTPUT2 and OUTPUTA Files 203 10 Upward Compatibility INDEX Introduction 203 Benefits 203 Theory 204 Inputs and Outputs 204 Examples 204 m Reduced OP2 File SET Consistency Check 206 Introduction 206 Benefits 206 Method and Theory 207 Inputs 207 Outputs 208 Guidelines and Limitations 208 Demonstration Example 209 Example Input Data TPL rop2s dat 209 Example Output 211 m SPC and SPCD Entries in Machine Precision 213 Limitation 213 m Reading of PUNCHed Long Field Format Bulk Data 214 m New Complex Conjugate Option for Matrix Multiplication 215 Examples 215 m Acceleration Loads ACCEL and ACCEL Bulk Data Entries 216 A Caution Concerning MSC Access Application Development 218 Divergent Thermal Results Error Correction O1 0768221 223 Displacement Output Filters 224 m Write Results Recovery for Subcases into Separate F06 Files 226 Example 239 Modules in MSC Nastran 2005 242 a DMAP Module Changes 242
178. l file operations and initialized with file control data FILNUM is returned to the calling routine 9 10 CHAPTER 9 223 Miscellaneous Divergent Thermal Results Error Correction Q1 0768221 This is an error correction for radiation boundary conditions in nonlinear heat transfer It can only occur when a RADBC entry is used in a nonlinear solution For problems where radiation heat transfer dominates conduction strange non physical results have been observed For most problems where radiation is modest no bad results will be observed In the January 2004 beta release this error was correct for the linear QUAD4 and TRIA3 elements This correction is now extended to the quadratic QUADS and TRIA6 elements in this release E 9 11 Displacement Output Filters The option to filter displacement output based on user defined threshold values is now available This option can be requested using the following new keywords in the DISPLACEMENT command Format DISPLACEMENT IMS RM f 1 f T2 f T3 f Ri 1 R2 f R3 f Examples DISP T1 1 0E 3 T3 1 0E 2 ALL DISP TM 1 0E 3 PRINT PLOT ALL DISP TM 1 0E 3 PRINT PLOT SORT2 20 Describers Meaning TM Translational Magnitude Filter T1 T2 T3 Translational Component Filters RM Rotational Magnitude Filters R1 R2 R3 Rotational Component Filters F Filter value Real 0 0 Remarks 1 Displacement components may be selected to control filtering
179. lable in dytran lsdyna and or features not yet supported by the translator will be ignored If NOERROR is entered and STOP 2 or 3 is not specified dytran lsdyna will be executed even though the complete MSC Nastran model may not have been completely translated NOERROR only be used by experienced analysts and then only with extreme caution Table 2 1 Case Control Commands Available in SOL 700 Case Contol Commands Available in SOL 700 ACCELERATION BCONTACT BEGIN BULK DISPLACEMENT DLOAD ECHO ELFORCE see FORCE ENDTIME Y new FORCE amp ELFORCE Y automatically produced in d3plot files no user control GROUNDCHECK Y MSC Nastran f06 only IC Y INCLUDE Y LABEL Y MSC Nastran f06 only LINE Y MSC Nastran f06 only LOAD Y for dynamic pseudo statics only 16 Table 2 1 Case Control Commands Available in SOL 700 Case Contol Commands Available in SOL 700 LOADSET Y MAXLINES Y MSC Nastran f06 only MPC Y NLPARM Y Psuedo static analysis only NLSTRESS Y Changed to STRESS PAGE Y In MSC Nastran only PARAM Y Only applicable parms are used PRESSURE SET SET OUTPUT PLOT SKIP SPC STRAIN STRESS SUBCASE Y See note Note Only one subcase can be selected for a particular SOL 700 analysis Many subcases may be entered in the input file but the one to be used must be selected using the SKIP ON and SKIP OFF Case Control commands If the SKIP ON OFF commands are not found or are in the wrong place the fi
180. lations can produce misleading or erroneous output and the analysis may terminate The MAXRATIO calculations have now been modified to take 2 by 2 pivoting into account Thus when 2 by 2 pivoting occurs maxratio calculations are not made on the DOFs in the 2 by 2 pivot If the maxratio vector is printed for this region it has an artificial value of 1 0 for these DOFs meaning that they will never be listed for reasonable values of the MAXRATIO parameter This produces MAXRATIO output which is more a true measure of the solution that has actually taken place inside the sparse direct factorization For analyses such as inertia relief using the SUPORT entry selected by PARAM INREL 2 or the new large displacement rigid elements or for solid elements using the interface spline elements it should no longer be necessary to specify the BAILOUT parameter The BAILOUT parameter is not recommended for production analysis only for model debugging activities It can mask models likely to produce low quality results When comparing results with those from a prior version you may see fewer high ratio DOFs in the regions where 2 by 2 pivots are used This is because the ratio messages were invalid for these DOFs on prior versions i 3 4 Performance Improvement in Modal Frequency Response for Large Frequency Ranges Modal frequency response is a relatively inexpensive method for calculating response quantities For large problems with large frequen
181. le endian or vice versa Msc2004 op4util x change v erbose m nnn from fname to fname To convert a file from one endian format to a specified endian format Msc2004 op4util Endian opt v erbose m nnn from fname to fname 9 4 Reduced OP2 File SET Consistency Check Introduction A procedure to reduce the size of the op2 file produced for use by MSC Patran in post processing operations has been available as a DMAP alter since the release of MSC Nastran 2001 With the release of MSC Nastran 2004 this procedure has been incorporated into the MSC Nastran DMAP and the alter is no longer required To employ the procedure MSC Nastran Case Control SET commands and DMAP parameters are used The procedure achieves its purpose by modifying the contents of two of the data blocks that are stored on the op2 file during POST output operations The GEOMI data block GRID point data record is modified so that it contains only a specified sub set of all of the grids available in the model Likewise the element connection data records in the 2 data block are modified so that they contain data for only a specified sub set of the elements available in the model The particular IDs to be retained in these data blocks are specified in SET list statements in the Case Control Section of the input data file The user specifies the SET ID for the grid point list by assigning its value to the OGRDSET DMAP parameter Si
182. like quality control than quantity control XINIT on the TOPVAR entry should match the mass target constraint so that the initial design is feasible Maximum design cycle DESMAX 30 as default is often required to produce a reasonable result More design cycles may be required to achieve a clear 0 1 material distribution particularly when minimum member size control used There are many solutions to a topology optimization one global and many local minimization It is not unusual to see different solutions to the same problem with the same discretization by using different optimization solvers or the same optimization solver with different starting values of design variables In a multiple subcase problem a Case Control command DRSPAN can be used to construct a weighting function via a DRESP2 or DRESP3 For example a static and normal mode combined problem the objective can be defined as 3 ol obj weightl 4 weight2 4 0 M where weight1 and weight2 are two weighting factors c is the calculated compliance and 2 is the calculated eigenvalue via 1 definition cg and 2 are the initial value of these responses The parameter BAILOUT 0 default may cause the topology optimization run to exit if near singularities are detected Users may increase the value of on TOPVAR to further prevent the singularity or set BAILOUT 1 to cause the program to continue processing with near singularities
183. long time This capability has been expanded to nonlinear elements in SOL 106 since MSC Nastran 2001 and to all nonlinear elements The element strain energy of each element was computed in the following way i seit sg Iit amet tur Eq 2 4 where SE represents the element strain energy of each element u represents the displacement vector F represents the element force vector and i represents the load increment Note that ij represents the most recent output load increment which controlled by INTOUT in NLPARM Bulk Data entry and i lt i This formulation made a limitation the correct result can only be obtained when INTOUT ALL in other words i i Otherwise the result is approximate when INTOUT YES or NO and ig lt i Specially it is very difficult to obtain a correct result when INTOUT NO In order to remove the above limitation the formulation of element strain energy has been modified in MSC Nastran 2005 It becomes i seit seis cho t er Eq 2 5 On the other hand the element strain energy is not output request dependent anymore in this release No matter if INTOUT is set to ALL YES or NO the correct element strain energy is calculated at the end of each loading case By the way the capability of ESE together with GPFORCE has also been added into SOL 400 when ANALYSISZNLSTAT in MSC Nastran 2005 Example The following example shows the difference of the element strain energy in MSC Nastran 20
184. ly supported in recent versions The offsets are handled by adding extra nodes at the offset coordinates and connecting RBE2 between original and offset coordinates Beam type 98 must be used rather than beam type 14 for offsets since beam type 14 does not have the fully 6 DOFs required for RBE2 That means beam plasticity cannot be combined with the beam offset The numbering of the extra modes starts at the highest node ID and increments by one above that CBEAM and CBAR internal loads stresses and strains were added for op2 xdb punch and f06 results This addition is applicable to UNIX Linux systems and to Windows systems if an Intel Marc 2005 or beyond version is used 42 Bolt elements were added to support MSC Marc both outside the USA and within the USA MSC Nastran Bulk Data entries MBOLT and MBOLTUS reflect these new additions The stacking direction for 3D composites were added with a new entry MSTACK Licensing for SOL 600 was changed to eliminate an extra license to spawn MSC Marc The MSC Marc license is adequate for that purpose In addition a standard MSC Nastran Nonlinear SOL 160 129 license was sometimes required this has now been eliminated Improved support for element material coordinate systems Improved non constant pressure loading which means that P1 P2 P3 P4 on the PLOAD4 entry will be used Before P1 was applied as a constant pressure n the element face The following errors have been correc
185. marizes the most important of these items Additions to the SOL 600 Executive Control Statement The new executive control statement is as follows SOL 600 ID PATH COPYR NOERROR OUTR op2 xdb pch f06 eig dmap beam NOEXIT STOP CONTINUE New items are dmap beam and CONTINUE An explanation of these items follows dmap The user will enter his own DMAP to create whatever type of output that is desired such as op2 xdb punch f06 For all other options DMAP is generated as needed internally by MSC Nastran beam The beam option must be specified if op2 xdb pch or f06 options are specified and beam internal loads are to be placed in any of these files The beam and eig options are mutually exclusive you cannot specify both CONTINUE is an option that specifies how MSC Nastran will continue its analysis after MSC Marc finishes To continue the analysis do not enter any STOP or OUTR options It is possible to perform more than one of these operations if necessary 0 MSC Nastran will continue the current solution sequence as normal For example if SOL 600 106 is entered SOL 106 will continue as normal after MSC Marc finishes Only 3D contact or materials supported by SOL 106 may be used 1 MSC Nastran will switch to SOL 107 to compute complex eigenvalues MSC Marc will generate DMIG matrices for friction stiffness and possibly damping on a file specified by pram marcfill name and time specified by param marcstif time This is ac
186. matrices The transpose flag DMAP parameter for both modules has been extended as follows Transpose Flag Meaning No Transpose Transpose Conjugate and No Transpose Conjugate and Transpose Examples 1 Compute D of A MPYAD 0 3 2 Compute X B C F where B is the complex conjugate of B SMPYAD A BC F X 3 1 1 0 0 2 3 Compute X U K U SMPYAD U KU X 3 3 A B where A is the complex conjugate transpose S 9 8 Acceleration Loads ACCEL and ACCEL1 Bulk Data Entries Traditionally MSC Nastran users have used the GRAV Bulk Data entry to apply acceleration loads The GRAV load is applied on the overall structural model as a uniform load Previously MSC Nastran was unable to apply an acceleration load that varied across the structure New Bulk Data entries ACCEL and have removed this limitation They allow the user to apply acceleration loads at individual grid points or ina specified region Both ACCEL and ACCELI loads are used in the same way as other load entries such as GRAV FORCE and MOMENT etc through the MSC Nastran Case Control commands Examples showing the use of ACCEL and are available in the TPL accelqr dat and accellqr dat Example SOL 101 TIME 10 CEND TITLE UNIFORMLY VARYING ACCELERATION LOAD SUBTITLE ACCEL LOAD TEST DECK AUTOSPC NOPRINT YES ECHO SORT SPC 1000 DISP PRINT ALL STRESS
187. milarly the SET ID value assigned to the OELMSET DMAP parameter specifies the SET ID for the element list A new feature has been added to this procedure This new feature ensures that all of the grid points connected to elements contained in the element list SET are also members of the grid point SET list This test is called the SET consistency check It is always performed when both the grid point set and element set are specified Ensuring that the sets are consistent eliminates the problem sometimes encountered in post processors when the op2 data is loaded Some post processors will refuse to load data for an element if the grid points connected to the element are not also present Benefits The enhancement to the reduced op2 file size feature ensures that the grid point list used to reduce the grid geometry data contains all of the grid points that are connected to elements in the element set used to reduce the element connection data Having a consistent set of data virtually eliminates the possibility of a post processor rejecting element data due to element connection grid point data being missing Until now it has been up to the user to ensure that the grid point set was consistent with the element set With this new release of MSC Nastran that burden has been removed from the user MSC Nastran will perform a consistency check of the grid point set and terminate the run if any grid points connecting the elements in the element set a
188. mining this table An example of this table is given below and the descriptions of information given in this table are shown in Table 2 3 Table 2 3 Nonlinear Iteration Summary Table STIFFNESS UPDATE TIME ITERATION TIME TIME 00000 02 00000 02 00000 01 00000 01 NO BIS ADJUST ITR NON TIME STEP DISP 0000 1 0000 2 0000 1 2 0 0 0 0 1 0000 1 2 1 1 NNER woune LINEAR 0 02 SECONDS 0 00 SECONDS ERROR FACTORS 00 00 3 30E 03 3 30E 03 59E 07 1 83E 09 1 10E 06 15 01 4 92 03 3 94E 03 90E 07 3 31E 09 8 20E 07 ITERATION MODULE SUBCASE 1130 STEP CONV ITR MAT AVG RATE DIV DIV R FORCE TOTL DISP E NO TOT TOT WORK AVG MAX WORK AT GRID C QNV KUD ITR 1 00 0 0 00 0 1 00 0 0 00 0 1 1 1 04 1 331E 05 2 63E 07 1 1 0 08 1 331E 05 2 63E 07 1 4 3E 04 3 098bE 04 1 42E 06 1 2 8 09 3 098 04 1 42E 06 1 644E 06 1 644E 06 9 204E 06 9 204E 06 1001 1001 1011 1011 m nero oooo DUNE Table 2 4 Explanation of Information in Nonlinear Iteration Summary Table TIME The Current Time It starts from 0 0 in the beginning of the 1st STEP and accumulates the value until at the end of the last STEP To each STEP the total time is determined by NDT and DT on the TSTEPNL Bulk Data entry TIME STEP NO Number of time increment including bisection Initialize to 0 in the beginning of each STEP TIME STEP
189. modal peak physical responses governed by the relationships of the type Uki peak lo dipeak KO peak 8 20 Itis interesting to note that substitution of the modal peak acceleration into the modal reaction equation results in 2 sear OVa Eq 8 21 CHAPTER 8 177 DDAM Processor The NAVSEA modal summation convention utilized in DDAM calculations follows the generic form N 2 Ril i21 sem Eq 8 23 Where R is a generic response quantity and r is the largest modal response quantity in the set 1 1 to N number of modes It should be noted that the index m is not necessarily the same for all physical responses The current version of the DDAM program performs the NRL summation following the latest specification in Reference 2 In this spec the modes are added up in decreasing order of modal mass rather than in increasing order of frequency The output now gives a summation order so that the user can follow the process Note that some modes may be included in the sum for one shock direction but not included for another direction Up to this point the value of the modal spectral velocities have not been discussed Due to the flexibility and finite mass of the ship structure onto which the structural system is mounted the value of is an empirical function of the modal and modal frequency o The actual formulae for
190. nd data interpretation aspects of the procedure In the process of modeling the subject structure a decision must be made at the outset to either employ sophisticated distributed mass modeling the more common approach or coarse lumped mass modeling The latter choice is one that permits adherence to the DDAM 50 modes criterion and is the type of analysis for which DDAM was developed However fidelity of the structural model with the actual structure may be severely compromised by using this approach This is especially true for plate and shell structures which tend to have a significant number of shell type modes which are lost in a lumped mass approach In more complicated shell structures the analysis is considered to be acceptable if enough modes are used such that at least 80 of the effective mass is accounted for This frequently be accomplished with significantly fewer than 50 of the modes and usually less than 50 modes This DDAM procedure allows the user to take either approach Redundant and geometrically distributed foundations require special consideration for meaningful DDAM analysis Since the shock environment is specified at one location distributed foundations must be referenced back to this single location For foundations that are not extremely distributed RBE2 constraints can be employed to effect the reference to the single point On more distributed systems however the mass and flexibility of the foundati
191. nd in the TPL Example Input Data TPL rop2s dat NASTRAN SYSTEM 361 1 5 210 Particular features of this example 1 the element ID set is SET 100 It has a thru range that includes non existent elements There is no informational output for this condition SET 100 is selected via param oelmset 100 bulk data entry 2 the point ID set is SET 200 It contains point ID 5 which does not exist in the model It also contains point 1005 which exists but is not referenced by an of the elements in SET 100 Both of these conditions cause informational messages to be generated SET 200 is selected via param ogrdset 200 bulk data entry 3 the element ID set SET 100 produces an element related point ID Set to be generated that contains several points that are not in the point ID set SET 200 This condition generates FATAL messages and causes termination of the run unless the OMSGLVL parameter is set to 1 which reduces the messages to WARNING level only and the run continues the element related point set is punched in case control SET format due to the presence of the param OPCHSET 1 bulk data entry This set could be used to replace the existing point ID set on a subsequent run and as long as the element set SET remained the same the two would produce a consistent set of data 4 Example Summary 1 SETs supplied are not consistent 2 Element related point set is punched in case control SET format dn dn dn dn dn
192. nd is used to increase the database capacity MSC Patran releases before 2001 should use the defaults for RECL and SIZE or database verification failures will occur logical key name MNF does not utilize UNIT or FORM Table 2 1 FORTRAN Files and Their Default Attributes CHAPTER 9 237 Miscellaneous Logical Key Physical Unit 1 Description Nona Name No Form Status Assignable Open Access Application SEMTRN sdir data f01 FORMATTED Input Data Copy Unit LNKSWH sdir data f02 UNFORMATTED Link Switch Unit MESHFL sdir data f03 FORMATTED Input Data Copy Unit SEMTRN sdir data f01 FORMATTED Input Data Copy Unit LNKSWH sdir data f02 UNFORMATTED Link Switch Unit MESHFL sdir data f03 FORMATTED Input Data Copy Unit LOGH out f04 FORMATTED Execution Summary Unit INPUT data dat FORMATTED Input File Unit PRINT out f06 FORMATTED Main Print Output Unit PUNCH out pch FORMATTED Default Punch Output Uniit authorize dat FORMATTED Authorization File INCLD1 Available for Use CNTFL Available for Use INPUTT2 INPUTT2 Unit OUTPUT2 UNFORMATTED OUTPUT2 Unit INPUTT4 INPUTT4 Unit OUTPUT4 UNFORMATTED OUTPUT4 Unit PLOT UNFORMATTED Plotter Output Unit BULKECHO out becho FORMATTED NEW YES YES SEQ Plotter Output Unit OUTPUT2F out 19 UNFORMATTED NEW YES SEQ Named OUTPUT2 Pattern OPCASE 22 FORMATED NEW YES SEQ Available for Use TOPDES out des 21 FORMATTE
193. not be achieved then bisection will be performed This method only updates matrix at every KSTEP convergent bisection solutions If the SEMI option is selected the program will update the stiffness matrix after the first iteration at each time step and then assume the normal AUTO option The stiffness matrix is always updated for a new STEP or Restart irrespective of the option selected The AUTO method has replace ADAPT to become the new default in the current release for ANALYSIS NLTRAN in SOL 400 For most of the problems we tested SOL 400 gives equal or better performance than that of SOL 129 However SOL 400 only output at user specified time steps in default In order to give output similar to that of SOL 129 user can assign a negative NO on TSTEPNL to retrieve the output logic from SOL 129 Nonlinear Iteration Summary Table for Nonlinear Transient Analysis in SOL 400 In order to allow the user to track the solution sequence during the nonlinear iteration a detailed Nonlinear Iteration Summary Table is output A line for each iteration is output on the F06 file during the nonlinear iteration Due to printing of the average and the maximum displacements the user will able to know the solution status before the end of the job This is useful for large nonlinear problems Even for small CHAPTER 2 49 Nonlinear Analysis problems the user will be able to know approximately how the analysis of a structural model performs by exa
194. ntrol data controls the final NRL summed DDAM result data Available data are STRESS FORCE DISPLACEMENT VELOCITY and ACCELERATION Other data are either not calculated in SOL 187 or are meaningless for DDAM Mode shapes will come out by default SOL 187 does not yet have the ability to use the XDB file for direct results access in MSC Patran Bulk Data Note In order for units to be totally consistent in analysis the MSC Nastran model must be formulated in units of inches for lengths and Ib sec in for mass It is not necessary for the x y or z axes to be correlated to any specific direction However the system must have individual axes that correspond to the fore aft athwartship and vertical directions i e You cannot have a system where the basic x axis points 45 degrees between the fore aft and vertical directions or output the whole model in a cylindrical system The input data file is required to have structure geometry property and material information as any model should Additionally the following information must be present A SUPORT entry is necessary to define the foundation reaction point the fixed base in all 3 translational degrees of freedom If the foundation is distributed as in most structures rigid elements or MPCs must tie all the foundation points to a single point This point must be in the residual structure for Superelements and in the A set this is the default for a SUPORTed degree
195. nual are now provided The new access key called BBB Tree method will be explained in the next release Subroutine Name DBFLOC 1 Entry Point DBFLOC 2 Purpose Locate and open an object among the open database s 3 Calling Sequence CALL DBFLOC FLEN FNUM KEYLEN IRET NAME Array input Dictionary entry of an object name Logical file number assigned to the FIL I NUM nteger output poned ohen CHAPTER 9 Miscellaneous The length of an instance for a keyed FLEN Integer output object or the total length in words for a sequential object ENUM Tie number of entries for keyed object or 1 for sequential objects The key length i for k KEYLEN _ Integer output E objects Return code conforming to IRET Integer output OPENR OPENS error codes or the additional 101 object format code is neither RECORD or VECTOR 102 dictionary entry could not be located among open database s 4 Method The object is first located is possible among the open databases by search from low to high logical data enumeration Once the first is located either OPENR or OPENS is used to depending upon its form The OPENR allows for application updates while OPENS for sequential objects opens for read only Statistics concerning the object size are also returned to the application Subroutine Name OPENC 1 Entry Point OP
196. o Figure 7 1 GRID I is on the damper journal and GRID is on the damper housing The two grids should be coincident and have parallel Cartesian coordinate systems The forces applied to the grids are based on the relative displacements and velocities of the grids determined from the previous time steps in the NASTRAN implicit time integration If a parallel centering spring is used then this separate spring is entered using the CELAS2 two ended element Y rti 7 Housing mS N d Journal N gt Z GRIDS NM I amp J N N AN Figure 7 1 Imbedding the SFD Model MSC Nastran Grid is on the Damper Journal and Grid J is on the Damper Housing Theory for General Squeeze Film Damper Model The squeeze film damper model is based on work originally performed at Case Western Reserve University CWRU It incorporates a numerical solution of the Reynolds lubrication equation for incompressible laminar isoviscous films that is described in Reference 1 The model is capable of handling the specified pressure boundaries at the feed supply and discharge drain ports of the SFD The SFD pressure distribution is determined using a one dimensional finite difference scheme The scheme is a 1 D adaptation of the 2 D finite difference method of Castelli and Shapiro Reference 2 The one dimensional finite difference approach permits the 152 account of static as well as dynamic deflect
197. o dynamics Added the following real valued words for initial displacement and velocity factors after the TID item on the TLOAD record and after the B item on the TLOAD2 record after Item Type Description UO Real Initial displacement factor for enforced motion VO Real Initial velocity factor for enforced motion 2 Table of Bulk Data entries related to element connectivity Changed names and header words for the following records MSC Nastran 2004 MSC Nastran 2005 Header Words Header Words BEAMAERO 2601 26 0 BEAMAERO 1701 17 0 CHEXAL 7708 77 369 CHEXAL 7908 79 369 Q4AERO 3002 46 0 AEROQ4 2002 20 0 T3AERO 2701 27 0 1801 18 0 Table of Data entry images related to constraints Changed the type of the enforced displacement value D on the SPCD and SPC records from single precision to machine precision Also added a null item in front preceding D 252 RESP12 Table of second level synthetic responses Inserted four more items after word 5 item REG Description Integer Method flag for BETA MATCH responses Real Constant to scale beta responses Real Constant to scale distance responses Real Constant to shift lower bound 10 3 CHAPTER 10 253 Upward Compatibility More Stringent Case Control Check Previous versions of MSC Nastran check the first 4 characters of the Case Control command For example to request displacement output any one of t
198. odal response reaches its peak value Thus the reaction force in the j direction is determined by the summation of individual modal reactions which are Fi Eq 8 14 Consider now the response to an impulsive shock occurring over the duration 0 lt lt which is much shorter than the period of any mode under consideration Integrating Eq 8 12 over the shock duration results in Eq 8 15 t where the term 18 negligibly small since the modal displacement hasn t had enough time to 0 develop and Vi Pigi t Eq 8 16 175 176 is the spectral velocity of the shock The free response of mode for gt is therefore q t sinet t 1 Eq 8 17 448 PjjV4 Cos Oif t q t O Vq SiN t t The physical significance of the structure and foundation reactions are determined by the modal superposition following Eq 8 7 with Ur 0 for gt and Eq 8 14 respectively Moreover internal loads and stresses on the structure are determined by stress recovery operations for the particular model described by the generic equation o K U Eq 8 18 According to NAVSEA requirements Reference 2 a shock spectrum summation method is adopted in which time phasing of modal responses is not considered In this approach the peak modal responses are utilized as qjpeak Pj V 7 qipeak V i Eq 8 19 qipeak Vai Individual
199. of freedom The translational directions of the SUPORT point define the directions for the shock response calculations so they should be in a rectangular coordinate system An option in the DDAM program allows you to orient the specific coordinate axes to the fore aft athwartship and vertical directions Though only translational directions are used for the shock response all 6 DOF may appear on the SUPORT entry If one direction has CHAPTER 8 161 DDAM Processor no unconstrained mass this happens a lot in test cases with few DOF that direction should be SPCed and not called out on the SUPORT entry If a massless direction is referenced you get a humorous MR MATRIX has NULL column error The eigenvectors must be normalized to MASS This is the default for the Lanczos solver on the EIGRL entry but not for other methods specified on the EIGR entry MAX normalization will result in incorrect modal masses and participation factors as the calculations use a shortcut for calculating the participation factors that relies on mass normalization Several parameters are available to control the analysis and to direct data to its required places There are two important and others somewhat less important parameters used in the bulk data file DDAM Control File In order for MSC Nastran to run the Fortran program correctly it is necessary to create a small control file that tells the program some information about your model The file
200. ollowing entries may not be specified OSETi SEQSETi SENOSET or PARAM NOSET Also those GRID and or SPOINT entries used to define the q set may be left in the Bulk Data section but it is recommended that they be removed In superelement analysis the calculation of component modes is attempted on all superelements including the residual structure Also all generalized coordinates for all superelements will become interior to the residual structure and also assigned to the q set in the residual structure In other words component modes may not be assigned interior to a superelement and they may not be removed constrained This feature is currently not supported with Multiple boundary conditions Design optimization SOL 200 Aerodynamic analyses SOLs 144 145 146 Cyclic symmetry analyses SOLs 114 115 116 118 Beers Restarts 106 Example In the following example the user defines six q set DOFs for natural frequencies up to 1200 cycles per unit time SOL 103 DIAG 8 15 CEND TITLE AUTOQSET DEMONSTRATION PROBLEM SUBTITLE TWENTY CELL BEAM SPC 1002 METHOD 1 BEGIN BULK EIGRL 1 1200 5 0 101 THRU 106 SPOINT 101 THRU 106 GRID 10000 0 0 0 0 0 0 1246 1 z 5 5 19 101 100 10000 10001 0 0 0 0 1 1 GL 1 1 18 PBAR 100 1000 0 31416 0 15708 1 1000 3 7 53 7 764 4 SPC 1002 10020 3 10000 3 ENDDATA The results of
201. omplished using MSC Marc s single file input MSC Marc Version 2005 and subsequent versions must be used The command line to execute MSC Marc is changed from np N or nprocd N to nps N where N is the number of processors The maximum number of processors for MSC Marc is 256 Continuation lines may not be entered for KIND 0 A similar option to create a single file MSC Marc t16 file is available starting with MSC Marc 2005 This option is picked using Bulk Data PARAM MARCOUTR 1 Be sure to have MSC Marc 2005 or later before using this option since it does not work properly with earlier versions Support for Intel and Digital Visual Fortran PC Version of MSC Marc Starting with MSC Marc 2005 an Intel version as well as a Digital Visual Fortran also known as Visual Fortran is available MSC Nastran 2004 r3 and MSC Nastran 2005 support both versions Distinctions between the two versions are only necessary for specifying the PATH to MSC Marc and for OUTR results processing The PATH can be handled as normal by using one of the path options on the SOL 600 Executive statement The OUTR options will be processed internally by MSC Nastran if the MSC Marc Intel version is used and will require an external t160p2 exe program if the Digital Visual Fortran version is used Beam Bar loads CHAPTER 2 41 Nonlinear Analysis stresses and strains are available using the Intel version and are not available using the Digital Visual For
202. on machine 1 and 4 processors on machine 2 host file name Name of a hostfile containing the same information as machine The format of hostfile is as follows for the example for machine machinel 2 machine2 4 A Windows example of the file sol700 pth for the PATH 3 case follows e sol700 dytran Isdyna run_dytran exe f latest_dytran lsdyna dytran lsdyna exe nproc 4 memory 20m steps 2 wdir f temp delete yes machine pc01 2 pc02 2 For the above example MSC Nastran will create the following command to spawn dytran lsdyna assuming your input file is named abcd dat Although the example appears like it is on multiple lines it is actually on a single line e Nsol700Ndytran Isdyna run dytran exe f latest_dytran lsdyna dytran Isdyna exe jid abcd dytr nproc 4 memory 20m wdir f temp delete yes machine pc01 2 pc02 2 Available PATH 3 options for UNIX Linux systems follows exe The full path to the executable for dytran lsdyna that is to be used Optional If exe is omitted the directory where the script or batch file resides first line of sol700 pth will be used and dytran lsdyna for UNIX Linux and dytran lsdyna exe for windows will be appended If exe is used it must be the second line in the sol700 pth file nproc Number of processors Default is to use NP on the SOL 700 line If NP and nproc are omitted the default is 1 bat Yes or no Run in background or forground default Leave out for steps 2 deb
203. on may be required in the structural model In these cases the foundation should be included in the analyzed model and the DDAM foundation points will be below the actual foundation Resilient mounting is not normally analyzed with DDAM In cases where equipment is resiliently mounted the mounts are generally assumed to have bottomed out In this case the mount points can be considered the foundation points DDAM analyses run on resiliently mounted systems are trivial exercises since all of the modal mass is accounted for in a single rigid body mode Flexible modes of the structure are not accounted for and all of the loads on the actual structure are frequently zero or close to zero For the process of load evaluation on a structure particular attention should be given to the mode by mode data provided in the verification file For cases where forces or stresses are found to be excessive the verification file can provide valuable guidance 170 In particular modes that contribute significantly to the overall loading can be identified These modes can then be visualized via PATRAN and the structure modified to change particularly detrimental modal behavior Another area where care must be taken are in models where significant mass is included that is not directly related to the structure of interest and is of lower frequency Reduction gear models that include significant runs of shafting are examples of this In these cases it is
204. opic LS Dyna material 3 isotropic with kinematic hardening LS Dyna material 5 soil and foam LS Dyna material 6 viscoelastic LS Dyna material 7 nearly incompressible rubber LS Dyna material 12 low cost isotropic plasticity model for solids LS Dyna material 13 non iterative plasticity model with failure LS Dyna material 14 soil and foam with failure LS Dyna material 15 Johnson Cook strain and temperature sensitive plasticity LS Dyna material 18 isotropic plasticity with rate effects LS Dyna material 19 strain rate dependent material model LS Dyna material 20 rigid material merges several rigid materials defined using MATD020 LS Dyna material 22 orthetropic material with brittle failure composites LS Dyna material 24 elasto plastic material with arbitrary stress strain curves and strain rate dependency LS Dyna material 26 Anisotropic honeycomb and foam LS Dyna material 27 Two variable rubber model LS Dyna material 28 Elasto plastic resultant formulation LS Dyna material 30 Shape memory superelastic material LS Dyna material 31 Frazer Nash rubber LS Dyna material 54 Enhanced composite material model LS Dyna material 57 Highly compressible low density foams LS Dyna material 59 Shell or solid composite models LS Dyna material 62 Confor viscous foam model LS Dyna material 63 Crushable foam with damping LS Dyna material 64 Strain rate dependent plasticity with
205. or eroding contact DYCONIGNORE Flag to ignore initial penetration or not 26 DYCONSKIPRWG DYHRGIHQ DYHRGOH DYENERGYHGEN DYTERMNENDMAS DYTSTEPERODE DYISTEPDT2MS DYMAXSTEP DYMINSTEP DYSHELLFORM DYSHTHICK DYSTEPFCTL DYRBE3 DYSHNIP DYNEIPH DYNEIPS DYMAXINT DYSTRFLG DYSIGFLG DYEPSFLG DYRLTFLG DYENGFLG DYCMPFLG DYIEVERP DYBEAMIP Controls whether or not to generate a few extra nodes to visualize a rigid wall Default hourglass viscosity type Default hourglass viscosity coefficient Hourglass energy calculation option Percent change in mass to end calculation Flag which determines whether elements will be eliminated at time TSMIN Time step size for mass scaling Maximum allowable time step Minimum time step that terminates the analysis Default shell formulation Specifies whether or not shell thickness changes with membrane straining Scale factor for internally calculated time step Control of RBE3 translation to MSC Dytran RBE3 or RBE3D Number of integration points for SOL 700 shells Control of integration point data output for solids Control of integration point data output for shells Another control of integration point data output for shells Control of strain tensor output Flag to include stress tensor in binary output file Flag to include effective plastic strain in binary output file Flag to include stress resultants in binary output file Flag to include internal energy and thickness
206. ormance especially for models whose complicated geometry presents problems to Geometric Domain ACMS Examples of such modeling include the following Spot welds via manual modeling technique Spot welds via CWELD elements Acoustic coupling via rigid elements and MPCs Large numbers of rigid elements and or MPCs for any purpose The following chart shows an example of the performance gain for a model that uses manual spot welding techniques Large model with manual spot welds 100 80 60 40 20 Elapsed Hours Geometric 4 DOF 1 DOF 2 DOF 4 Domain Processors CHAPTER 3 75 Numeric Enhancements DOF Domain ACMS performs at least as well as Geometric Domain ACMS for models that do not feature these special characteristics as shown in the following chart Large Typical NVH Model m Geometric Domai m DOF Domain o 2 5 o 2 No of Processors Other important features of DOF Domain ACMS include A Component Modal Synthesis theory identical to that used in ACMS and in all other MSC Nastran CMS techniques Residual vectors that are employed at every component at every level in order to maximize the accuracy of the CMS DMP Distributed Memory Parallel available up to eight processors providing excellent parallel speedup Full compatibility with MSC Nastran superelement techniques including External Supe
207. out the world All of our courses emphasize hands on computer laboratory work to facility skills development We specialize in customized training based on our evaluation of your design and simulation processes which yields courses that are geared to your business In addition to traditional instructor led classes we also offer video and DVD courses interactive multimedia training web based training and a specialized instructor s program Course Information and Registration For detailed course descriptions schedule information and registration call the Training Specialist at 800 732 7211 or visit www mscsoftware com Preface xiii Internet Resources MSC Software www mscsoftware com MSC Software corporate site with information on the latest events products and services for the CAD CAE CAM marketplace Simulation Center simulate engineering e com Simulate Online The Simulation Center provides all your simulation FEA and other engineering tools over the Internet Engineering e com www engineering e com Engineering e com is the first virtual marketplace where clients can find engineering expertise and engineers can find the goods and services they need to do their job CATIASOURCE plm mscsoftware com Your SOURCE for Total Product Lifecycle Management Solutions xiv CHAPTER 1 MSC Nastran 2005 Release Guide Release Guide Introduction 1 1 Release Guide Introduction MSC Nastr
208. oven valuable in anumber of applications and the new FUNC BETA type on the DRESP2 entry merely simplifies the data preparation for this case by creating the following design task Minimize F Xg CiXg Subject to 118 where C and C are user input values that have default values of 100 and 10 0 respectively C is used to scale the objective function and C is used to offset the constraint bound from 0 The y quantity is computed so that the maximum constraint for all the response is equal to another user input value C Emax max Where is the value of the maximum response for the initial design The default value for C is 0 005 creating a maximum constraint that is just equal to the default value of DOPTPRM parameter GMAX The matching of analysis results with user specified values is performed by converting the user input data to one of two user specified formulations a Matching Using Least Squares or b Matching Using Minimization of the Maximum Deviation Matching Using Least Squares The least squares technique converts the user input into an objective function of the following form m 2 j 1 j where r is a response from a DRESP1 and r is a user defined target response There are no constraints spawned by this formulation but the user is permitted to specified any other desired constraints in the standard fashion Matching Using Minimization of the Maximum Deviation The second formulation is a
209. plot ALL STRESS CORNER plot ALL STRAIN plot ALL SPC 1 LOAD 1 NLPARM 1 CMETHOD 101 BEGIN BULK param marcfill dmig002 param mrmtxnam kaax param mrspawn2 tran param mrrcfile nast2 rc PARAM OGEOM NO PARAM AUTOSPC YES PARAM GRDPNT 0 EIGC 101 HESS x99 NLPARM 1 10 AUTO Jp P YES PLOAD4 T 121 800 PLOAD4 1 122 800 rest of deck is the same as any other SOL 600 input file CQUAD4 229 2 271 272 293 292 CQUAD4 240 2 272 273 294 293 ENDDATA The full input for this example can be obtained from MSC Nastran development The name of the input file continu2 dat Support of Complex Eigenvalue Analysis SOL 600 now supports complex eigenvalue analysis via the CMETHOD Case Control command and the EIGC Bulk Data entry In addition four new Bulk Data parameters have been introduced param marcfill dmig002 This means that a file named dmig002 will be used It contains stiffness matrix terms possibly from a set of unsymmetric friction stiffness matrices param mrmtxnam kaax This means that in the dmig002 file use DMIG matrix terms labeled kaax or case does not matter 36 param mrspawn2 tran This means that the primary MSC Nastran run will spawn another MSC Nastran run to compute the complex eigenvalues The name of the command is nastran nas is always used and the characters specified by this parameter are added to the end of nas Thus we get nas tran nastran param mrrcfile nast2 rc T
210. possible to get 80 of the modal mass entirely in shafting modes In these cases it may be necessary to increase the modal mass percentage to assure that you are getting 80 of the mass of the portion of model of interest A Note on Symmetry While the NAVSEA 3010 document does not exclude running a symmetric model it does not provide any guidelines to do so There are some important considerations when using symmetry Among them The modal mass must be doubled to calculate the shock coefficients properly Both symmetric and anti symmetric modes must be included in the final NRL sum Symmetry plane boundary points must be constrained with SPC entries which violates the SUPORT assumption in this DDAM or connected to the SUPORT entry with RBE elements which incorrectly marks them as foundation input points The MSC Nastran NRL sum module DDRMM cannot combine modes from different NASTRAN runs without a modification to the DMAP alter Cyclic symmetry involves calculating all of the proper harmonics calculating the modal masses correctly and then summing all of the different harmonic modes in the final NRL sum Because of all these caveats it is neither advisable nor easy to use this DDAM processor for symmetric models However if it is to be used there are several modifications that must be made to the procedure including manually calculating modal masses and the resulting shock factors The user should be very car
211. pring 2 266 8 266 800 Ib Step 9 Perform the NRL Sum of the Spring Forces Note that the NRL sum reduces to a trivial summation for this 2 mass case Spring 1 909 200 444 900 1 354 100 Ib Spring 2 606 200 266 800 873 000 Ib Step 10 Calculate the Nodal Displacements and Velocities Since the deflection of each mode is an orthogonal mode shape the displacements velocities and accelerations are related by Ra d The accelerations can be simply calculated from d qe id ia W 1 Mass 1 Mode 1 Mass 2 Mode 1 Mass 1 Mode 2 Mass 2 Mode 2 CHAPTER 8 DDAM Processor 183 302994 Tage n 37 87 g 37 87 386 4 in oo 1634 89 72 sec 37 87 386 4 5 1 818 in 89 72 606248 000 10104 8 101 04 386 4 89 72 101 04 386 4 R 5 4 850in 89 72 711743 3000 88 97 g 88 97 386 4 _ in 196 6 HA C _ Ay 8897 3864 _ 2 8894 in 196 6 266771 6000 25908 44 46 386 4 _ 196 6 44 46 3864 _ 2 RW lee 4445 in 196 6 Fa AT W Ay 0 Ay XT 75 Q1 F3 2 W 775 04 Bets A12 Vi 95 A12 EX d s 2 2 ee Bm 2 75 184 Step 11 NRL Sum the Velocities Displacements and Accelerations Like the forces this is a trivial summation for this sample problem Mass 1 x 21 818 8894 2 707 in V 2163 1 174 9 338 0 in sec A 37 8
212. r Ur 0 10 U P The matrix partitions are defined as follows NE 11 2 T 9 1 Kuu T 1 Kir E 91K KuKu Kil Eq 8 9 5 1 A Mr Kj K Kjj Mj My Kj Kj E 0 KE Ki T PA P T 0 I0 CHAPTER 8 DDAM Processor The physical significance of the above noted matrix partitions is that P is the matrix of participation factors is the total rigid body mass referenced to U and 0 1 the constraint matrix is null due to the determinate foundation U For the case of DDAM requirements response of a structure to an imposed foundation motion Ur V Us t Eq 8 10 is sought The array serves as a directional vector for the applied motion history Us t for example if it is directed in the U sense x direction then T 1 I 0 0 From the upper partition of Eq 8 8 the modal response equation is obtained as UM di 192041 EPMTYUSC Eq 8 11 The individual mode equations are 2 7 qilt o q i r Eq 8 12 for mode excited by a shock in the j direction The foundation reaction forces determined by the lower partition of Eq 8 8 as Mrr T USC Eq 8 13 In DDAM analysis the second term is Eq 8 13 is neglected due to the assumption of an extremely short duration applied shock so that the U t is zero by the time each m
213. re missing from it This improves user productivity in several ways CHAPTER 9 Miscellaneous Less time is spent re running jobs to get the correct amount of reduced output for the op2 file Less time is spent correcting the grid point set as all of the missing grid points are identified by MSC Nastran and a revised SET can be punched at user option Method and Theory The theory behind this new feature is very simple Each and every grid point connected to the elements in the element set should be present in the grid point set The method is equally simple A list containing all of the points present in the model is created Next each of the elements in the model is checked to see if its ID is in the element ID set If itis then each of the grid points that the element connects is flagged in the point ID list Once all of the elements have been processed each point in the point list that has been flagged as touched by an element is tested to see if it is present in the grid point ID set If a point touched by an element is not present in the grid point set then a FATAL error message is issued and the job will be terminated The grid point set is also checked to see that every point in it was flagged during the element set processing that produced the element related grid list For each point in the grid point set that is not in the element related grid point list or is not in the model aWARNING message is issued The element related point ID li
214. re would be no fatal messages generated 9 5 CHAPTER 9 213 Miscellaneous SPC and SPCD Entries in Machine Precision In previous versions enforced displacement values defined on the SPC and SPCD entries were always treated as single precision numbers Under this enhancement the SPC and SPCD entries have been converted to machine precision format real values of these entries will be maintained in machine precision during all operations in static analysis leading to more accurate computation of loads Limitation The entry GMSPC used for p element analysis still remains in real single precision in the bulk data interpretation l 9 6 Reading of PUNCHed Long Field Format Bulk Data Large field input format requires at least two lines for each Bulk Data entry So for an entry with fields 5 9 blank a continuation entry is necessary A fatal error results if a long field entry does not contain at least one continuation entry However if requested the PUNCHed bulk data from this run would still be created with the bad long field format entry This restriction has now been removed and a single line long field format entry is now acceptable Its PUNCHed bulk data would also be created consistent with the input bulk data entry 9 7 CHAPTER 9 215 Miscellaneous New Complex Conjugate Option for Matrix Multiplication The MPYAD and SMPYAD modules have been enhanced to compute conjugate matrix multiplication for complex
215. reation of the design variables and then discusses other features that have been adapted for topology optimization TOPVAR Topological Design Variables To select a topologically designable region the user needs to specify a group of elements All elements referencing a given property ID are made topologically designable with the Bulk Data entry TOPVAR Topology design variables are automatically generated with one design variable per designable element The basic format for TOPVAR is 1 2 3 4 5 6 7 8 9 10 TOPVAR ID LABEL PTYPE XINIT XLB DELXV POWER PID Field Contents ID Unique topology design region identification number Integer gt 0 LABEL User supplied name for printing purpose Character PTYPE Property entry name Used with PID to identify the elements to be designed Character PBAR PSHELL etc XINIT Initial value Real XLB lt XINIT Typically XINIT is defined to match the mass target constraint so the initial design does not have violated constraints For example if the mass target is 30 then it is suggested XINIT 0 3 XLB Lower bound Real Default 0 001 CHAPTER 6 137 Optimization Field Contents XLB Upper bound real Default 1 0 DELXV Fractional change allowed for the design variable during approximate optimization Real gt 0 0 default 0 2 see Remark 3 POWER A penalty factor used in relation between topology design variables and element
216. relements Fully integrated with the SPCD method of enforced motion in SOL 111 Fully integrated with Acoustic Panel Participation in SOL 111 fluid structure interaction Available in SOLs 103 111 and 200 Available with external superelements 3 2 Improvements for Geometric Domain Based ACMS Error corrections include the following Improved robustness by correcting error related to free floating i e unconnected scalar points Fixed key errors in the ACMS interface with transient analysis and MAXMIN data recovery Fixed errors related to CWELD elements Fixed key error related to parallel execution for acoustic models In addition enhancements were made to make grid based ACMS work with the new External Superelement capability CHAPTER 3 77 Numeric Enhancements Improved Matrix Diagonal Diagnostics for 2x2 Pivots MAXRATIO Matrix to factor diagonal ratios are a long standing tool that help determine model integrity in MSC Nastran With the increased use of Lagrange Multiplier Technique LMT variables 2 by 2 pivoting employed by the sparse direct solver in MSC Nastran has become more common In the event of 2 by 2 pivoting the matrix to factor diagonal ratio was computed incorrectly prior to MSC Nastran 2004 r3 with the value of 1 0 used as the factor diagonal value for that DOF If the stiffness value was greater than maxratio the DOF would fail the maxratio test In these cases MAXRATIO calcu
217. responses compliance and fractional mass and topology design variables are shown if Figure 6 5 Also in this figure the design variable history shows the external element ID associated with the internal design variable ID 139 140 INTERNAL DRESP1 RESPONSE LOWER UPPER ID ID LABEL BOUND VALUE BOUND 1 1 COMPL N A 1 4162 02 INTERNAL DRESP1 RESPONSE LOWER UPPER ID ID LABEL BOUND VALUE BOUND 2 2 FRMASS N A 3 0000E 01 3 0000E 01 ck ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ckckokck SUMMARY DESIGN CX GLE HISTORY ee ee ee ee DESIGN VARIABLE HISTORY INTERNAL EXTERNAL DV ID ELEMENT ID LABEL INITIAL 3 1 2 1 1 3 0000 0 2 4000 0 2 2 3 0000 0 2 4000 0 3 2 3 0000 0 2 4000 0 4 4 3 0000 0 2 4000 0 5 TOPVAR 3 0000 0 3 6000 0 6 6 3 0000 01 3 6000 0 7 7 3 0000 0 2 4000 0 8 8 3 0000 0 2 4000 0 9 9 3 0000 0 2 4000 0 10 10 3 0000 0 2 4000 0 Figure 6 5 New Output in jobname f06 PARAMETER DESPCH specifies when the optimized Bulk Data entries are written to the PUNCH file for sizing and shape optimization In topology optimization DESPCH is used to specify
218. rge mass approach For the enforced displacement and enforced velocity applications in transient analysis this improved scheme yields much better correlation between the results obtained from these two approaches than existed in earlier versions It also results in improved correlation with the corresponding results obtained from the Lagrange multiplier technique LMT Initial Condition Specification for Enforced Motion Usage via SPC SPCD Enforced acceleration or enforced velocity usage in transient analysis via SPC SPCD specification requires integration to compute the corresponding enforced velocities and or displacements This integration involves the use of initial conditions Prior to MSC Nastran 2005 there was no way for the user to specify the initial conditions for the enforced degrees of freedom DOFs in these cases Starting with MSC Nastran 2005 this facility is now available With this feature the user can specify initial displacements for enforced DOFs in the case of enforced velocity usage via SPC SPCD and can specify initial displacements as well as initial velocities for enforced DOFs in the case of enforced acceleration usage via SPC SPCD The initial displacement and velocity values are specified via corresponding factors in two new fields that have been added to the TLOAD1 and TLOAD2 Bulk Data entries Details CHAPTER 5 111 Dynamic Analysis will be clear from the description of these expanded entries in the MSC Nastran Q
219. rst subcase encountered will be used and the others ignored SUBTITLE Y TITLE Y TSTEP Y Same as TSTEPNL TSTEPNL Y VELOCITY Y WEIGHTCHECK Y In MSC Nastran only CHAPTER 2 17 Nonlinear Analysis Table 2 2 Bulk Data Entries Available in SOL 700 Bulk Data Entries Available in SOL 700 Fatal Error AXIC AXIF AXSLOT BAROR BCBPDY BCHANGE BSURF BCBOX BCPROP BCMATL BCONP N BCTABLE Y Revised BLSEG N CBAR CBEAM CBEND CBUSH CCONEAX CDAMP1D CDAMP2D CELAS1D CELAS2D CFLUID N CGAP N CHACAB N CHEXA Y 8 Nodes only CONM2 Y 2 CUN OE COE E ee Se GZ Table 2 2 Bulk Data Entries Available in SOL 700 Bulk Data Entries Available in SOL 700 Fatal Error CONROD CORDIC CORDIR CORDIS CORD2C CORD2R CORD2S CORD3G CPENTA Y 5 Nodes only CQUAD4 Y COUADS Y 4 Nodes only CQUADR Y CQUADX N CREEP N CROD X CSHEAR N CTETRA Y 4 Nodes only CTRIA3 Y CTRIA6 Y 3 Nodes only CTRIA3R Y CTRIAX CTRIAX6 CTUBE CVISC CWELD CSPOT Y New LS Dyna Weld CFILLET Y New LS Dyna Weld CHAPTER 2 19 Nonlinear Analysis Table 2 2 Bulk Data Entries Available in SOL 700 Bulk Data Entries Available in SOL 700 Fatal Error CBUTT Y New LS Dyna Weld CCRSFIL Y New LS Dyna Weld COMBWLD Y New LS Dyna Weld DAMPGBL Y New for Dynamic Relaxiation DAREA Y DEFORM DELAY DMI DMIAX DMIG DPHASE DTI ECHOOFF ECHOON ENDDATA Y EOSPOL Y New Equation of state FORCE FORCEI1 FORCE
220. s at POINTs above those from of the previous velocities 202 The PKS and PKNLS methods can be applied in SOL 200 DIAG 39 can be used in the PK and PKNL methods to provide insight into the iterative root extraction process Additional output is available with PKS and PKNLS as well but it can be voluminous for most problems Example pkswep dat This is the HA145A example of the MSC Nastran Aeroelastic User s Guide with a single subcase applying the PKS method The FLUTTER Bulk Data entry in this case is 1 2 3 4 5 6 7 8 9 10 FLUTTER 3 PKS 1 2 3 L 5 01 The PKS method is selected and maximum frequency of 5 0 Hz is used in the sweep and the sweep region is divided in 100 equally spaced frequencies ranging from 0 0 to 5 0 HZ The output flutter summary is headed by FLUTTER SUMMARY CONFIGURATION AEROSG2D XY SYMMETRY ASYMMETRIC XZ SYMMETRY ASYMMETRIC POINT 1 MACH NUMBER 0 0000 DENSITY RATIO 1 0000E 00 METHOD PKS Where the METHOD PKS indicates that the PKS method has been selected 9 3 CHAPTER 9 203 Miscellaneous Little Big Endian Variable Endian OUTPUT2 and OUTPUTA Files Introduction Major MSC Nastran customers typically use the program in batch mode on a remote mainframe computer or cluster requiring transfer of the model and results data between the remote machine and the local workstation The amount of results data is often significant so binary file formats are prefera
221. s calculated for designed elements only FRMASS 1 0 if all design variables 1 0 The COMP and FRMASS response types are provided to facilitate the specification of the classical topology optimization task of minimizing the compliance of a loaded structure while limiting the mass to some percentage of the maximum allowable amount In MSC Nastran s implementation these responses be applied generally so that the COMP response could lead to a constraint and the minimization of FRMASS could be an objective New and Modified Design Optimization Parameters DOPTPRM Two new design optimization parameters are added for topology optimization in SOL 200 as shown in Table 6 5 A new parameter TCHECK is used to turn on off a filtering algorithm to prevent the checkerboard like material distribution Another parameter TDMIN is introduced to achieve mesh independent solutions control the size of members in the topology optimized design and therefore the degree of simplicity in terms of manufacturing considerations In addition a number of existing DOPTPRM parameters have different default values for topology optimization as opposed to Sizing Shape optimization as shown in Table 6 6 As described in BIGDOT Optimizer on page 147 the BIGDOT optimization algorithm is available for topology optimization problems with many gt 2000 designed elements This is selected by setting DOPTPRM parameter METHOD to 4 Table 6 5 New DOPTPRM Design
222. s determine the flutter eigenvalues by performing a sweep of reduced frequencies ranging from kest 0 0 through kest x CREF OMAX Velocity 10 OMAX specifies the maximum frequency in Hz If this field in an integer it corresponds to the current NVALUE parameter that provides the number of eigenvalues to be extracted If the field is blank the default is the number of modal degrees of freedom in the flutter analysis Outputs The output from the PKS and PKNLS methods are quite similar to those of the PK and PKNL methods The METHOD selected is printed in the flutter summary DIAG 39 can be used display the eigenroots for each estimated k value but this will produce a large amount of output In SOL 200 formatted prints of the density value are now the actual density value rather than the density ratio Guidelines and Limitations tis suggested that the PK and PKNL methods be the primary flutter algorithms with PKS and PKNLS reserved for cases where the former methods do not appear to be performing well An attribute of the new methods is that they can produce more roots at a given velocity than there are normal modes This is deemed a valid result but is counter to most current flutter methods including those used in MSC Nastran This can produce a difficult sorting task when more or fewer roots are extracted at one velocity than were extracted at an earlier velocity MSC Nastran attempts to cope with this and puts the new root
223. s if user requests Direct matrix input such as K2PP and EPOINT are supported in nonlinear transient analysis Support grid based reordering for a faster decomposition to both nonlinear static and transient analyses Support thermal excitation in the nonlinear transient analysis Two new Bulk Data entries and TMPSET have been added for this new feature in nonlinear transient analysis The GPFORCE and ESE output are supported in the nonlinear static analysis The same restart capability which had been introduced in MSC Nastran 2004 is also available to the nonlinear transient analysis now A more flexible output method for the nonlinear transient analysis User can use a new parameter NLPACK to control the output and restart time steps Allow simulation of the same output logic and format of SOL 129 by specifying a negative NO on the TSTEPNL Bulk Data entry Limitations for the Current Release In this pre release the following capabilities are not supported Initial Condition in the nonlinear transient analysis The nonlinear normal modes and the nonlinear buckling analysis RFORCE and Creep The arc length method input by NLPCI Bulk Data entry The stress data recovery of the layer composite elements Only the left rotation vector method LANGLE 3 is allowed to process large rotation in nonlinear transient analysis The nonlinear static analysis ANALYSIS NLSTAT and the nonlinear transient analy
224. sis ANALYSIS NLTRAN cannot be mixed in one SUBCASE The line contact The first 5 items will be supported in a future release However the last item line contact will not be support in SOL 400 It will be replaced by the general contact capability in SOL 600 CHAPTER 2 45 Nonlinear Analysis In the following sections how the new capabilities work in the current release is discussed Case Control Commands SUBCASE STEP and ANALYSIS The STEP command was first introduced in MSC Nastran 2004 for the nonlinear static analysis of SOL 400 In this release it has been expanded to support the nonlinear transient analysis and again for SOL 400 only User can specify different type of analysis at different SUBCASE and or STEP by using the Case Control command ANALYSIS Until now ANALYSIS Case Control command supports the following 3 keywords They are LNSTATIC NLSTATIC the default and NLTRAN The combination of SUBCASE STEP and ANALYSIS commands will provide a mechanism for defining the multiple load steps running multiple independent cases and at same time allowing the user to specify multiple types of analyses in one job The following examples illustrate the manner in which the SUBCASE STEP and ANALYSIS commands are used With one SUBCASE and multiple steps each step defines the total new external load and other characteristics for the step which will be applied by the completion of the step The solution of any STEP
225. st can be punched in Case Control SET format There are two other options available when using this new feature Both options relate to how the content of the final point ID set list is created that controls the content of the GEOMI grid point data record One option simply uses the element related list of point IDs as the grid point set For this option set consistency is guaranteed The other option merges the input grid point set into the element related list of points and uses the merged set of points as the grid point set For this option set consistency is not checked Inputs The new set consistency check operation is automatically performed in MSC Nastran when both the element set and the grid point set are specified The reduced 2 file size capability already available in MSC Nastran 2004 is controlled by the OELMSET and OGRDSET parameters and the specification of the associated Case Control SET lists The OELMSET parameter value identifies the ID of the SET containing the IDs of the elements that are to be retained on the op2 file The OGRDSET parameter value identifies the ID of the SET containing the IDs of the grid points that are to be retained on the op2 file Several additional parameters have been introduced with the new set consistency check feature All of the parameters associated with the reduced 2 file size and set consistency check feature are now summarized 207 208 OELMSET Integer Default 0 I
226. stiffness will be used in a geometric nonlinear analysis PARAM MAXLP Specifies maximum number of iterations for element relaxation and material point sub increment process PARAM NLAYERS Specifies the number of layer for through thickness integration in the material nonlinear analysis PARAM NLTOL Selects defaults for CONV EPSU EPSP and EPSW for the Bulk Data entry NLPARM PARAM PH2OUT Requests phase II outputs for a nonlinear analysis PARAM NLPACK Control the total output time step in one output package see Outputs on page 52 e PARAM NDAMP Specifies the value a numerical damping of the method in SOL 400 Case Control Commands e ANALYSIS Selects solution method for an analysis step see Case Control Commands on page 54 NLRESTART Requests a restart execution at a specific solution point for SOL 400 see Restart on page 50 NLSTRESS Requests the form and type of the nonlinear element stress output STEP Delimits and identifies an analysis step see Case Control Commands on page 54 Bulk Data Entries Specifies the hyperelastic material properties for an element CHAPTER 2 55 Nonlinear Analysis MATSI Specifies the stress dependent material properties for an element TSTEPNL Defines a set of parameters for nonlinear transient analysis iteration strategy TTEMP Defines a time dependent dynamic temperature distri
227. stran input file is named abcd dat or abcd bdf then jid abcd Unless explicitly specified using the STOP option dytran lsdyna will be executed from MSC Nastran on any computer system capable of doing so which includes most UNIX systems and Windows systems For dytran lsdyna to run it must be installed properly licensed and accessible from the directory where the MSC Nastran input data resides BASE must be provided in the environment Executive Control Parameters The required ID may be one of several valid solution sequence integers or names shown in Solution Sequences on page 144 of the MSC Nastran Quick Reference Guide for the SOL statement Examples are 129 and NLTRAN The following solutions are available for Phase I of this project 101 106 109 129 and their equivalent names All items on the SOL 700 ID after ID itself may be specified in environmental variables This may be done in any manner environmental variables can be set They may be set by the MSC Nastran user at run time or by the system administrator when MSC Nastran is installed Any values specified on the SOL statement override those in the environment Environmental variables are fully described in the MSC Nastran 2005 Installation and Operations Guide A keyword file is available to describe the format of each variable The variable is normally set in the system wide rc file a user s rc file a local rc file or in a script used to submit MSC Nastr
228. support services on the web by telephone or e mail Go to the MSC Software website at www mscsoftware com and click on Support Here you can find a wide variety of support resources including application Preface xi examples technical application notes available training courses and documentation updates at the MSC Software Training Technical Support and Documentation web page United States Telephone 800 732 7284 Fax 714 784 4343 Munich Germany Telephone 49 89 43 19 87 0 Fax 49 89 43 61 716 Rome Italy Telephone 390 6 5 91 64 50 Fax 390 6 5 91 25 05 Moscow Russia Telephone 7 095 236 6177 Fax 7 095 236 9762 Send a detailed description of the problem to the email address below that Frimley Camberley Surrey United Kingdom Telephone 44 1276 67 10 00 Fax 44 1276 69 11 11 Tokyo Japan Telephone 81 03 6911 1200 Fax 81 03 6911 1201 Paris France Telephone 33 1 69 36 69 36 Fax 33 1 69 36 45 17 Gouda The Netherlands Telephone 31 18 2543700 Fax 31 18 2543707 Madrid Spain Telephone 34 91 5560919 Fax 34 91 5567280 corresponds to the product you are using You should receive an acknowledgement Xii that your message was received followed by an email from one of our Technical Support Engineers MSC Patran Support mscpatran support mscsoftware com MSC Nastran Support mscnastran support mscsoftware com MSC Nastran
229. t ASSIGN statement the following rules apply a If there is no current entry for the specified log name a new entry in the DBset tables will be created If there is an existing entry for the specified log name the ASSIGN parameters will modify that entry instead of creating a new one the default file name or if this is a second or subsequent ASSIGN statement for the same log name the previously specified file name or default name if none was previously specified will be used If the same logical key is used on more than one FORTRAN file ASSIGN statement the following rules apply a If filename2 is omitted or specified as or and if the UNIT describer is omitted the ASSIGN parameters will modify the system default entry for the logical key establishing the new defaults for any subsequent ASSIGN entry for the logical key Note however that any entries previously created with the same logical key will not be modified by the new parameters specified on this ASSIGN statement b If the value specified by the UNIT describer matches the value for an entry created by a previous ASSIGN statement with a UNIT describer then if the logical key values are different a UFM will be generated if the logical key values are the same the previous entry will be updated instead of having a new entry created c Ifthe value specified by the UNIT describer does not match the value for an entry created by a previous
230. t on the POST output file unless there is a SPCF Case Control command present Refer to the tables under the POST parameter description in Parameters on page 608 for a list of the output items supported by each post processor 5 Any data generated by a case control output request is automatically included in the oplist of the POST command If output data is not wanted for a particular case then the characters NO should be the first two characters of the keyword in the oplist For example NODISP specifies that displacements are not to be posted to the output file even though they have been requested via the DISP Case Control command Alternatively the related POST parameters may be used For example to avoid outputting any displacements whatsoever to the op2 file use a PARAM OUG NO Bulk Data entry 6 Certain data e g geometry is always generated and is not dependent upon the presence of a case control command in the input data The POST command affects the placement of this data on the external file only insofar as the selection of the post processor defines the value of the POST DMAP 230 parameter value The actions described in Parameters on page 603 under the POST parameter description will prevail for the particular value of POST associated with the selected post processor The primary purpose of the POST command is to give the user more control over subcase dependent output data being stored on the external OUTPUT file
231. table If an output item supported by a particular post processor is described in Parameters on page 603 but is not listed here then the POST command cannot be used to control its output to the external file Case Command Output Item oplist Keyword Displacements NO DISPLACE DISP Forces of Single Point Constraint NO SPCFORCE SPCFORCE Element Forces NO FORCES ELFO FORCE Element Stresses NO STRESS ELST STRESS Element Strain Energy NO ESE ESE Grid Point Force Balance NO GPFORCE GPFORCE Stress at Grid Points NO GPSIGMA STRESS CHAPTER 9 229 Miscellaneous Case Command Output Item oplist Keyword NOJ GPEPSILON STRAIN NOJ PLYFAILURE STRESS NOJEKE EKE NOJEDE EDE NO MPCFORCE MPCFORCE Strain Curvature at Grid Points Composite Element Failure Indices Element Kinetic Energy Element Energy Loss Multi point Constraint Forces NOJPLYEPSILON STRAIN NOJSTRAIN STRAIN NO GPSTRESS GPSTRESS NOJ GPSTRAIN GPSTRAIN Applied Loads NOJ LOAD No items to be output NONE Composite Lamina Strains Element Strains Grid Point Stresses Grid Point Strains Composite Lamina Stresses NO PLYSIGMA STRESS 4 Output data items must have been generated via the appropriate case control command in order for the data to be available for post processing options For example the specification of SPCF in the oplist of the POST command will not produce forces of single point constrain
232. ted Work hardening slope specified by MATEP was ignored Gasket materials could not be defined with other solid element materials Eigenvalue analysis after a nonlinear analysis sometimes gave wrong results FTYPE variable of the BCPARA entry was not translated More than one NLSTRAT entry could not be provided RFORCE did not translate properly MSC Marc s ORIENTATION option was not employed correctly CPENTA pressures were sometimes applied to the wrong face BEGINBULK caused an abort CHAPTER 2 43 Nonlinear Analysis Pre release of the Nonlinear Transient Analysis in SOL 400 Introduction In order to improve the nonlinear solution procedure in MSC Nastran a general nonlinear solution sequence SOL 400 has been introduced since MSC Nastran 2004 to support nonlinear static analysis In MSC Nastran 2005 a new capability the nonlinear transient analysis has been added to SOL 400 Since some capabilities are still under development and the V amp V test has not been completed this is only a pre release and its intention is to get user feedback Eventually this solution sequence will include all nonlinear analyses such as the nonlinear static analysis the nonlinear transient analysis the nonlinear buckling analysis the nonlinear normal modes analysis and other related solution procedure such as the linear static and transient analysis into one general solution procedure In the final run SOL 400 is go
233. th static and transient is directly handled as thermal strain in SOL 400 when computing the element forces Unlike all the other linear and nonlinear analyses the thermal load is not created to the nonlinear elements anymore in SOL 400 In MSC Nastran 2004 the thermal effect has been added into nonlinear static analysis in SOL 400 To support it in nonlinear transient analysis two new bulk data entries are created in the current release They and TMPSET Basically TTEMP is to define a time dependent dynamic thermal field T t in the same form as TLOADI Atthe same time TMPSET is to define a group of grid points which refers to the same TTEMP Bulk Data entry Pleasesee New Bulk Data Entries and 52 TMPSET on page 64 for the details of these two new bulk data entries By using TTEMP and TMPSET the whole model can be separated into finite sub regions and each sub region can have its own temperature distribution pattern If it is necessary user can also make every grid point as a independent sub region or make the whole model as a single sub region Same as nonlinear static analysis TEMP INIT and TEMP LOAD commands are used in the Case Control file to define the temperature input in nonlinear transient analysis The SID of TEMP LOAD can refer to TTEMP and TMPSET but not the TEMP INIT The temperature of any grid point whose ID is not listed in the TMPSET will be interpolated linearly in the same way as
234. the f06 show that six q set are insufficient to capture the residual vectors as shown by the messages below REAL EIGENVALUES BEFORE AUGMENTATION OF RESIDUAL VECTORS MODE EXTRACTION EIGENVALUE RADIANS CYCLES GENERALIZED GENERALIZED NO ORDER MASS STIFFNESS 1 1 1 881936 04 1 371837 02 2 183346E 01 1 000000E 00 1 881936 04 2 2 3 011058 05 5 487311E 02 8 733327E 01 1 000000E 00 3 011058E 05 3 3 1 524259 06 1 234609 03 1 964941 02 1 000000 00 1 524259 06 4 4 4 816616 06 2 194679 03 3 492940 02 1 000000 00 4 816616 06 5 5 1 175494 07 3 428547 03 5 456702 02 1 000000 00 1 175494 07 6 6 2 435711 07 4 935292 03 7 854762 02 1 000000 00 2 435711 07 7 7 4 506449 07 6 713009 03 1 068409 03 1 000000 00 4 506449 07 USER WARNING MESSAGE 9144 SEMR4 THERE ARE NO Q SET DEGREES OF FREEDOM LEFT TO ACCOMMODATE ANY RESIDUAL VECTORS USER INFORMATION NO RESIDUAL VECTORS WILL BE COMPUTED USER ACTION SPECIFY AT LEAST 6 MORE Q SET DEGREES OF FREEDOM USER WARNING MESSAGE 9145 RESLOAD THERE ARE NOT ENOUGH Q SET DEGREES OF FREEDOM DEFINED TO ACCOMMODATE ALL OF THE COMPUTED EIGENVECTORS AND OR RESIDUAL VECTORS USER INFORMATION THE LAST 1 MODE S ABOVE WILL BE TRUNCATED USER ACTION SPECIFY AT LEAST 1 MORE Q SET DEGREES OF FREEDOM Dynamic Analysis CHAPTER 5 REAL MODE NO USE gt R EIGENVALU
235. the sensor location so that accurate sensitivities are of benefit The example was exercised in three different runs 1 Using ANALYSIS DFREQ 2 Using ANALYSIS MFREO with 9 normal modes and 4 residual modes available in MSC Nastran 2004 these modes are produced from three inertia loads and one applied load 3 Same as 2 except an additional residual vector is created based on the DRESP1 at the sensor location Figure 6 3 Visual Sensor Model Figure 6 4 shows the percent error in the sensitivity results across a range of frequencies where the error is computed as the difference in the modal frequency response compared to the direct frequency response normalized by the direct frequency response It is seen that the single additional residual vector has a pronounced effect in reducing the error Percent Error CHAPTER 6 127 Optimization SENSITIVITY ERROR No Residual from Adjoint amp Residual from Adjoint Frequency Hz Figure 6 4 6 5 Multiple Boundary Conditions for DFREQ MFREQ in SOL 200 SOL 200 has been capable of supporting multiple boundary conditions MBC for statics normal modes buckling and aeroelasticity for some time However dynamic frequency response analysis of structures subjected to multiple loads under different boundary conditions SPC MPC and or SUPORT has not been supported in SOL 200 until recently With MSC Nastran 2004 r3 SOL 200 is capable of performing sensitivity
236. the spectral quantities are presented in Reference 4 and the form of the equations are presented effective mass M ai in Format of Coefficient File on page 185 An interesting property of modal effective mass is that the sum of the individual will approach the total actual mass of the system as the number of modes N approaches the complete set for the mathematical model The summation will terms M exactly approach the total system mass if no mass is allocated to the foundation degrees of freedom Um U Ifmass is allocated to the foundation the summed effective mass will approach the total mass minus the foundation mass For DDAM analyses NAVSEA allows utilization of a truncated mode set which provides a minimum of 50 of the total number of modes of the system Because this requirement is excessive for modern large scale finite element models described by thousands of degrees of freedom NAVSEA accepts analyses that contain at least 80 of the model s effective modal mass The number of modes required to achieve this amount is highly model dependent but frequently involves less than one hundred modes compared to thousands required by the 50 criterion 8 4 Worked Two Mass Problem Problem Consider the following arrangement 80001 20 70 Ib sec in i N J my m 6000 lb 15 53 Ib sec in k 500 000 Ib in 1 k 200 000 Ib in f DU ae x
237. thms for Flutter Analysis Introduction Two new flutter solution algorithms are available in MSC Nastran 2005 These two methods complement the existing PK K K E and PKNL methods and are referred to as PKS and PKNLS The S signifies sweep and is meant to indicate that these methods use a sweep technique to determine the flutter eigenvalues By contrast the PK and PKNL methods employ an iterative approach that relies on roots found at one estimated k reduced frequency value to estimate the roots at the next estimated k This iterative process sometimes encounters a flutter analysis task that cannot be solved completely so that only a limited set of results are obtained When this occurs a message is printed USER WARNING MESSAGE 4581 FA1PKE PK FLUTTER ANALYSIS FAILED TO CONVERGE FOR LOOP xx ROOT yy Figure 9 1 shows a comparison of extracted and estimated reduced frequency values and shows how the iterative scheme can break down It is seen that most of the estimated roots line up in straight lines that are almost invariant with respect to the estimated frequency However one root starts at a kext of 3 0 and falls rapidly to kext 0 0 crossing the 45 degree line near kext 1 0 It is this root that gives the P K algorithm trouble since its order changes as kest increases violating an assumption of the algorithm 200 vel 200 kts e
238. tion specified with the new DRESP2 functionality If multiple DRESP1 responses are invoked with FUNC BETA each must be a scalar quantity If a single DRESPI entry is invoked with FUNC BETA the assumption is that this one DRESP1 generates multiple responses e g displacements at a series of frequencies or stresses for a number of elements Examples dr2beta1 dr2mtch1 and dr2mtch2 Three examples are provided with this delivery The first is dr2betal and is similar to the acoustic optimization task of Acoustic Optimization in Chapter 7 of the MSC Nastran Design Sensitivity and Optimization User s Guide modified to utilize the new BETA function on the DRESP2 The DRESP2 in this case has the form DRESP2 100 BETA BETA min 10000 1 047 100 DRESP1 1 CHAPTER 6 121 Optimization Where 1 10000 C2 1 047 and C3 100 have been selected to produce an initial design that is similar to that in the user s guide Note that the only user specified constraint in this case is on the weight since the remaining constraints are spawned from the DRESP2 as is the beta design variable The dr2mtch1 file is a simple eigenvector optimization task that seeks to minimize the difference between three components of the first eigenvector while using a more traditional constraint technique to force a match between measured and analytical results for the third eigenvector The original form of the design task was developed as degvnt01 dat and is described
239. tion for the Nonlinear Element Strain Energy A 2 1 MSC Nastran Explicit Nonlinear SOL 700 Beta Capability Introduction MSC Nastran Explicit Nonlinear also known as SOL 700 is a new capability introduced as a preliminary capability in MSC Nastran 2005 This is the first phase of adding explicit nonlinear dynamics to MSC Nastran The Phase 1 effort primarily is intended to solve highly nonlinear structural crash and impact problems Fluids air bags seat belts and passengers are not a part of Phase 1 and will be added in subsequent phases Although Phase 1 primarily addresses crash and impact loading usually described by initial velocity input other types of dynamic loading are also supported SOL 700 works in a manner similar to SOL 600 but instead of spawning MSC Marc a special version of the well known LS Dyna program is spawned Like SOL 600 SOL 700 contains an internal translator MSC Nastran input data is translated to MSC Dytran input data during the IFP portion of MSC Nastran Later in IFP LS Dyna is spawned Special subroutines have been added to LS Dyna to accept MSC Dytran format input data similar to LSTC s keyword input data in the standard version of LS Dyna Inside LS Dyna the MSC Dytran input data is stored directly in memory and converted to a structured LS Dyna style input file which is the old style type of input without headers LS Dyna then continues with computations to produce output results for hig
240. to unsymmetric laminates are included in the nonlinear analysis Also in this version the temperature dependent composites capability has been extended to the nonlinear QUADR and TRIAR composite elements nonsmeared approach is also available for the QUADR and TRIAR element types This approach is a more general approach in that the laminate properties are not smeared as in the classical lamination theory but evaluated during the element matrices calculation using an integration by layer The benefit of the nonsmeared approach is that it will allow for future implementation of material nonlinear capabilities Both the smeared and nonsmeared approaches are valid for symmetric and unsymmetric laminates Non uniform element grid point temperature and temperature gradient support by the QUADR TRIAR is another difference compared to the constant element temperature QUAD4 TRIA3 element types Temperature dependent QUAD4 TRIA3 composite models can be easily converted to equivalent QUADR TRIAR models by adding the NASTRAN 5 command to the input file Note that the nonlinear QUADR TRIAR element types are limited to temperature dependent composites Additional nonlinear analysis capability for these element types is planned for in future releases The following table summarizes the user interfaces for invoking the temperature dependent composite capabilities for the composite element types Parameter QUAD4 TRIA3 QUADR
241. tors The COEFF entry is formatted like a NASTRAN statement i e ten eight character fields The entry looks like 1 2 3 4 5 6 7 8 9 10 COEF nsurf nstruc nplast VF 1 VE VEG AF AFQ AFG VA VB VC AA AB AC AD nsurf ship type Allowable values are SUB submerged and SURF surface ship nstruc mounting location Allowable values are DECK HULL and SHELL nplast elastic or elastic plastic factors Allowable values are ELASTIC and ELPL The i in the VF and AF refer to the directions 1 fore aft 2 athwartship and 3 vertical A blank entry or a entry in any field will use the default value from the program source for that value 186 In addition to the COEF entry defining coefficients there is a CUTOFF entry that defines the modal mass cutoff percentage That entry looks like CUTOFF pref pref is the cutoff weight percentage for the modal mass calculation Enter as a percentage not a decimal fraction i e 85 instead of 85 Note that you still have the option of overriding this value when you run the program pref 100 Use all available modes nn Make spectral values zero for all modes beyond the one that first exceeds nn percent of the total mass A sample coef dat file to analyze different surface ship equipment using the elastic plastic factors might look like special elastic plastic surface ship
242. tput for an or DFREQ SOL 200 job with MBC is identical to those with a single boundary condition Hence the output example is not shown here Guidelines and Limitations The SPC MPC and SUPORT conditions are used to determine whether a new boundary condition has been encountered e DFREQ and subcases cannot be mixed The restriction on a single modal transient subcase remains I 6 6 Benefits of Matrix Domain ACMS in SOL 200 Matrix Domain Automated Component Mode Syntheses MDACMS is the latest Lanczos solver introduced in MSC Nastran 2005 You can find a detailed discussion in ACMS Now Available in the Matrix DOF Domain on page 74 You can use this new feature in a SOL 200 run by specifying the DOMAINSOLVER ACMS partopt dof command It is available for Analysis MODES and or MFREQ and both serial and parallel processing are supported A parallel run is activated when DMP nandn gt 1 This new feature has been tested with an NVH optimization task with a 4 2M dofs for an eigenanalysis up to 300 Hz that produced 1960 modes Three separate runs were performed The following plot shows that a parallel 4 processor MDACMS SOL 200 job achieves more than 6 times speedup relative to a Geometric Domain ACMS GDACMS SOL 200 run reduced time from 37 Hrs to 6 Hrs while the serial MDACMS SOL 200 run reduces to 14 Hrs for a 2 5 times speedup MDACMS vs GDACMS in SOL200 Elapsed Time
243. tran run using TABLEST and TABLES entries or a pre existing file can be used depending on the value of PARAM MRAFFLOR The extension mat will be added to Name If this isa new file it will be saved in the directory from which the MSC Nastran execution is submitted If a pre existing file is to be used it can either be located in the directory where the MSC Nastran execution is submitted or in the MSC Marc AF flowmat directory Improved Parallel Processing for SOL 600 In previous versions of SOL 600 the basic MSC Marc input file had to be split up into as many MSC Marc input files as processors to be used MSC Nastran 2005 incorporates the capability to use a new MSC Marc feature called the Single File Parallel file For this to work properly the user must obtain MSC Marc 2003 beta 2 or 40 later to run in combination with MSC Nastran The interface to use this capability specifies KIND 0 or blank on the PARAMARC entry as shown below the other options are still available but should be considered obsolete Format 1 2 3 4 5 6 7 8 9 10 PARAMARC ID KIND NPROC Example To create 4 parallel processes using MSC Marc s single file input PARAMARC 5 4 Field Contents ID Identification number of the PARAMARC entry Not presently used Integer KIND Designates how parallel domains are created Integer gt 0 Default 0 0 Parallel processing is acc
244. tran version The PC version for OUTR processing can be selected by the new MSC Nastran Bulk Data parameter MARCWIND Integer Default 0 Determines which Windows version of MSC Marc Digital Visual Fortran or Intel is to be used for those versions of MSC Marc that support both versions This option is only necessary if any OUTR option is used If the Intel version is used all t160p2 work is accomplished inside MSC Nastran If the DF version is used a separate t160p2 exe program is required and must be on the PATH This parameter applies only to SOL 600 used in combination with MSC Marc 2005 or later versions The MSC Marc version prior to 2005 always used the Digital Visual Fortran version 0 The Digital Visual Fortran version of MSC Marc is used 1 The Intel version of MSC Marc is used Other SOL 600 Items PBUSHT support has been added for nonlinear springs TABLED1 can be used to specify the load deflection curve The PBUSHT TBLED1 data is mapped to MSC Marc s SPRINGS option with table driven force deflection curves This capability will work with MSC Marc 2003 or 2005 Buckling In prior SOL 600 versions only one nonlinear load case could be run prior to a buckling eigenvalue extraction Now multiple nonlinear load cases can be run before requesting buckling eigenvalue extraction Improved beam offsets MSC Nastran 2005 supports beam and shell plate offsets they were not supported in some earlier versions and only partial
245. uations Reference 5 is a text that follows the shock class taught by Rudy Scavuzzo and Henry Pusey It provides a lot of background on testing and requirements as well as many theoretical and analytical aspects of underwater shock and DDAM i 8 3 Theoretical Background Consider a structural system Figure 8 1 described by a set of U displacements a subset of which corresponds to a foundation interface Um If the foundation interface is redundant let it be assumed that the foundation undergoes rigid body displacements that is no foundation warping Thus the foundation interface is related to a six degree of freedom DOF reference point displacement subset U through a multi point constraint relationship Um Gm U Eq 8 1 The remaining displacements in the U set may be interrelated in a variety of ways depending on the particular structure s configuration and approximating assumptions such as Guyan Reduction or Generalized Dynamic Reduction When all constraints and reductions are applied the structural displacement state is described in terms of a set denoted here as the U set which is partitioned as follows U Eq 8 2 r The subset U is comprised of discrete grid point displacements and generalized displacements remaining after reduction depending upon the choice of approximating assumptions CHAPTER 8 173 DDAM Processor Up Um F ye Figure 8 1 In terms of
246. ug Yes or no Outputs many messages from the script or batch file CHAPTER 2 13 Nonlinear Analysis memory Amount of memory example memory 20m 20 MD steps Number of steps 1 or 2 default is 2 Two steps means that Isdyna is executed twice once to form the structured input file and again to analyze it Although steps 1 is faster there are some models that fail using the steps 2 option wdir Working directory Default is directory where MSC Nastran input resides copy Yes or no Input and output files are copied from wdir to the input directory Default is yes delete Yes or no LS Dyna scratch files are deleted or not Default is yes cluster Yes or no If yes is specified the job will be initiated on the machine that the user is logged on to but the analysis is performed on the cluster nodes that are specified in machinefile If the default of off is used the job will run on the local machine and the machines listed in the machine file depending on the number of processors specified This option is not available for early SOL 700 releases Default is no mpipath The MPI install directory if you wish to used a non default MPI directory mpirun The MPI run command you want to use If entered it overrides the default MPI run command on your machine as well as the command in mpipath A UNIX Linux example of the file sol700 pth for the PATH 3 case follows users joe sol700 run_dytran nproc 4 memory 20m steps 2
247. uick Reference Guide This enhancement will greatly help users in performing enforced motion studies with a variety of scenarios It should be noted here that the initial conditions for the enforced DOFs mentioned here are distinct from and may be used in conjunction with the initial conditions for independent DOFs that may be specified by a TIC Bulk Data entry 112 CHAPTER 6 Optimization Composite Ply Strength Ratio Response Type for the DRESP1 Entry B New FUNC tions for the DRESP2 Entry E Transformation of Approximate Optimization Task to a Feasible Design Residual Vectors Based on Adjoint Loads B Multiple Boundary Conditions for DFREQ MFREO in SOL 200 Benefits of Matrix Domain ACMS in SOL 200 B ADS Optimizer B Topology Optimization Beta Capability BIGDOT Optimizer A 6 1 Composite Ply Strength Ratio Response Type for the DRESP1 Entry Introduction The CSTRAT response type has been added to the DRESP1 entry to support the specification of composite ply strength ratios in a SOL 200 design task Benefits Strength ratio output was provided as an additional available response in MSC Nastran 2004 see Chapter 5 6 in the MSC Nastran 2004 Release Guide This is a direct failure indicator and as such is an ideal response for the design of composites Input The existing DRESP1 entry is used to identify the new CSTRAT response type See the MSC Nastran Quick Reference Guide for a complete des
248. ulk data has been read in equivalent BAR and BEAM elements are created from the data supplied by the PBRSECT and PBMSECT entries These equivalent element definitions are printed out to the f06 output file Guidelines 1 BRP for CP and OP must start or end branching from OUTP BRP must not start or end from another BRP 2 BRP must not branch out from the end of OUTP This rule covers both CP and OP 3 ForCPandOP a T rs where rs denotes a positive real single precision number must be present even if the thickness for every segment is separately defined This thickness will be used for all segments which do not have specific thickness defined for them 4 When PT id1 id2 is utilized to define the thickness of a segment the id1 and id2 must be next to each other on the SET1 or SET3 A warning message will be issued if this guideline is not observed For a design optimization analysis the PBRSECT and PBMSECT entries are referenced by the design variable property relation entries DVPREL1 Dimensions that can be taken into the design optimization analysis include Overall Width input W for PNAME field of DVPREL1 This is available for GS CP and OP Overall width is computed as X1 max x1 Both x1 and X1 are collected by examining X1 of all POINT entries involved Overall Height input H for PNAME field of DVPREL1 Also available for GS CP and OP Overall height is computed as 2 X2 Both 2 and
249. umber of design variables is in the thousands and above Input BIGDOT is available in MSC Nastran by specifying METHOD 4 on the DOPTPRM entry Table 6 7 contains the meanings of the four options for this parameter 148 Table 6 7 Meaning of the METHOD Parameter on the DOPTPRM Entry Description Method of Feasible Directions using DOT default for non topology optimization problems Sequential Linear Programming using DOT Sequential Quadratic Programming using DOT BIGDOT default for topology optimization problems The remaining DOPTPRM parameters that govern the behavior of the optimizer are identical between DOT and BIGDOT so that no additional inputs are required Output The output from BIGDOT algorithm itself is controlled by existing DOPTPRM parameter IPRINT There are no other outputs that are affected by BIGDOT Guidelines and Limitations The BIGDOT algorithm is intended for problems with many design variables For problems with fewer than one thousand variables the DOT or ADS algorithms are recommended As mentioned in the Introduction to this section the BIGDOT algorithm is available to users that have purchased the Topology Optimization TO option for MSC Nastran This complements the existing Design Optimization DO option in the following way 1 If the user has acquired the DO option only this enables standard shape and sizing optimization and topology optimization with a limited number of des
250. update the defaults for subsequent ASSIGN statements for the same logical key value See Remark 7 Requests that the file associated with log name or logical key UNIT be deleted at the end of the run Requests that the file associated with logical key UNIT if it exists before the start of the run be deleted CHAPTER 9 233 Miscellaneous Describer Meaning DELZERO Requests that the file associated with logical key UNIT be deleted at the end of the run if it is zero length that is if it does not contain any data STATUS Specifies whether the FORTRAN file is being created STATUSZNEW or has been created prior to the run STATUS OLD If its status is not known then STATUS UNKNOWN is specified FORM Indicates whether the FORTRAN file is written in ASCII FORM FORMATTED or binary FORM UNFORMATTED BIGENDIAN LITTLEENDIAN LTLEND lt ostype gt format See Remark 11 DEFER Defers opening creating the specified file That is the file will not be opened created during MSC Nastran initialization The file must be explicitly opened by the module or DMAP accessing the file using for example FORTIO before it can be used sys spec System specific or machine dependent controls For DBset files these control I O performance For FORTRAN files these are controls for IBM MVS type computers only See Remark 14 RECL 1 The size of a block of input output information specified in words See Remark 15 SIZE s The number of blo
251. ures for topology optimizations The response is usually used as an objective to maximize structural stiffness in static design problems A new DRESP1 FRMASS is introduced to define the mass fraction of topology designed elements The DRESP1 WEIGHT is the total weight of all structural and non structural mass For topology optimization tasks DRESP1 FRMASS response is recommended to define a mass reduction target in a design constraint The POWER field on the TOPVAR entry has a large influence on the solution of topology optimization problems A lower POWER often produces a solution that contains large grey areas area with intermediate densities 0 3 0 7 A higher value produces more distinct black and white solid and void designs However near singularities often occur when a high POWER is selected 142 A parameter TCHECK on DOPTPRM is used to turn on off the checkerboard free algorithm The default of TCHECK 1 activates the filtering algorithm This default normally results in a better design for general finite element mesh However if high order elements and or a coarser mesh is used turning off the filtering algorithm may produce a better result The parameter TDMIN is mainly used to control the degree of simplicity in terms of manufacturing considerations It is common to see some members with smaller size than TDMIN at the final design since the small members have contributions to the objective Minimum member size is more
252. very KSTEP iteration at a time step interval 64 New Bulk Data Entries and TMPSET TTEMP Temperature Distribution of Transient Response for Dynamic Thermal Excitation Define a time dependent dynamic thermal distribution in the same form as TLOAD1 T t AG F OJ where A T defines the temperature field and T t is the temperature distribution for use in the nonlinear elements in nonlinear transient analysis Format 1 2 3 4 5 6 7 8 9 10 TTEMP SID GROUP ID TID Example 1 2 3 4 5 6 7 8 9 10 TTEMP n 101 31 Field Contents SID Temperature set identification number Integer gt 0 GROUP_ID Temperature group identification number Integer gt 0 or 1 TID Identification number of TABLEDi entry that gives F t Integer gt 0 Remarks 1 SID is defined in Case Control file by TEMP LOAD SID 2 This entry is used in SOL 400 only when ANALYSIS NLTRAN nonlinear transient analysis and the temperature load is applied It only applies to the nonlinear elements in the Residual SEID 0 There should be only one temperature set for each STEP 3 GROUP_ID determines the time dependent distribution of temperatures It references to TMPSET Bulk Data entry to define all grid points which reference the same TABLEDi entry Each grid point can have its own GROUP ID if it is necessary GROUP_ID 1 means all grid points are in one group and reference to the same TTEMP Bulk Data entry
253. xample three EX03 is modified from the standard QA file NLTTL002 This model only has 1 QUADA element and 2 TRAI3 elements Its major purpose is to show the various combinations of TTEMP and TMPSET inputs in nonlinear transient analysis for the thermal effect All the bold font statements are entries related to the temperature related inputs ID MSC 400 8 15 TIME 60 EALL ALL ALL G 47 ral Il H E 1 UBTITLE ECHO NONE ES D LN H 2 EX03 5 999999999 EMPERATURE INITIAL UBCASE 1 nalysis NLTRAN tep 1 TSTEPNL 1 5 2 TEMPERATURE LOAD DISPLACEMENT SORT1 REAL ALL nlstress all stress all step 2 TSTEPNL 1 SPC 2 TEMPERATURE LOAD DISPLACEMENT SORT1 REAL ALL nistress all stress all SUBCASE 2 analysis NLTRAN step 3 THERMAL LOAD TI Q4 T3 MODEL 1 3 4 EST FOR NONLINEAR TRANSIENT ANALYSIS TT EMP AND TMPSI EX03 ET TSTEPNL 1 SPC 2 TEMPERATURE LOAD 5 DISPLACEMENT SORT1 REAL ALL nistress all stress all step 4 TSTEPNL 1 SPC 2 TEMPERATURE LOAD 6 DISPLACEMENT SORT1 REAL ALL nistress all stress all SUBCASE 3 analysis NLTRAN step 5 TSTEPNL 1 SPC 2 TEMPERATURE LOAD 7 DISPLACEMENT SORT1 REAL ALL nistress all stress all step 6 TSTEPNL 1 SPC 2 TEMPER
254. y direction displacement Positive entry typically used for 1 g compensation The OFFSET2 value represents an eccentric damper housing in the vertical direction and is typically used to compensate for the 1g displacement of damper supported by a centering spring 154 Squeeze Film Damper Example The following example demonstrates the use of the new NLRSFD nonlinear force The model is shown in Figure 7 2 The MSC Nastran input file is shown in Listing 7 1 The unbalance load of 20 Gm cm is used to excite the structure The resulting nonlinear forces are shown in Figure 7 3 Rotor Grid 101 Support Grid 102 NLRSFD 4 Spring to Ground Figure 7 2 Model Listing 7 1 NASTRAN SOL 109 CEND TITLE Simple test model SOL 109 No damping 5 UNSORT 5 Sore ceno Results requests f cceree SET 101 100 101 DISP PRINT PUNCH SORT2 101 SET 102 101 102 ELFORCE PRINT PUNCH SORT2 102 5 5 999 NONLINEAR 1 SUBCASE 200 LABEL 20 gm in unbalance 100 0166 6667 100 0166 6667 123456 003 CHAPTER 7 Rotor Dynamics 2 pi 2 386 08858 in sec 2 No Ip onStat forSpinDir HorizK VertK HorizK VertK HOA LO SHORT DLOAD 200 OUTPUT XYPLOT XGRID YES YGRID YES XTITLE TIME SEC YTITLE SFD FORCE X XYPLOT NONLINER 101 T1 YTITLE SFD FORCE Y XYPLOT NONLINEAR 101 72 BEGIN BULK 5 1 386 4 PARAM WIMASS258799
255. zation 180 Y P ERE Xis eigenvectors m individual masses Gia poule e 1 0873 20 70 2929 15153 Pubs i 2 2 2 X11 X21 m 00873 20 70 2329 15 53 Xana Py 124 2212 z 2017 20 70 1008 15 53 2610 X12 m X22 m 2017 2070 1008 15 53 Step 4 Calculate the Modal Masses Unlike the participation factors the modal masses are not normalization dependent Note that the modal masses are really weights 2 Xiam gt Xia m X y 2 11m 21m M 1 2 C0873 20 70 2829 15 53 _ 11 368 Ib X11 m Xa m C0873 20 70 2329 15 58 2 Xo 1m 2 X221mM2 2017 2070 1008 15 53 _ 2 631 1b X12 m X22 m 2017 2070 1008 15 53 Step 5 Choose the Shock Coefficients We will choose surface ship deck inputs These correspond to the coef dat file in the sample directory They do not represent any real spectrum and only serve to demonstrate the DDAM solution methodology 50 VA 120 AB 40 50 10 10 F A factor 1 0 Athwartship factor 1 0 Vertical factor 1 0 CHAPTER 8 181 DDAM Processor Step 6 Calculate the Spectrum Inputs The equations found here are of the same form as some formal specifications The values however are simply for demonstr

MSC.Nastran 2005 - MSC Software Corporation

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