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FEM Practicals (Lent 2014-15)

1. Frame Primary Variable Deformed Variable ne nmtercechone Output Variable _ List only variables with results l Description indicates complex Point loads at nodes X Values True distance X distance Normalized distance Y distance Sequence ID O 7 distance Point moments at nodes Y Values R Reaction force at nodes Step 1 Load Step RM Reaction moment at nodes Frame 1 Step Frame Spatial displacement at nodes Field output variable UU2 cman JR Rotational displacement at nodes Note Result option settings will be applied to calculate result values for the current step and frame Plot Cancel Invariant Component 24 Module 1 7 To access the data so that you can compare the predictions to those of ordinary beam bending theory select Tools gt XY Data Edit Al_Deflection_Elastic_1D Copy and paste the data into Excel The results should look as shown in Fig 110 0 01 0 01 0 02 0 03 Yernical Displacement m 0 04 1 Dimensional FEM Model Analytical Model 0 05 0 0 2 0 4 0 6 0 8 1 x Position m 25 Module 1 Solution b e Start ABAQUS CAE At the Start Session dialogue box click Create Model Database e From the main menu bar select Model gt Create The Edit Model Attributes dialogue box appears name the model Cantilever_3D A MODULE PART Under the Part mo
2. By default the results will be saved in C Temp I MODULE VISUALISATION 1 From the main menu bar select View Toolbars gt Views Choose plane 1 2 from the Views dialogue box Fig I1 VIEWS x EEEE 2 From the main menu bar select Results Field Output The Field Output options box will open From the list of options select U from the primary variables and U2 as the component Fig 12 a Click OK b Select Contour from the Select Plot State dialogue box and Click OK c The deformed cantilever beam will be displayed 32 Module 1 MS Field Output Step Frame Step 1 Load Step Frame 1 Sten Frame Primary Variable Deformed Variable Output Variable List only variables with results sl Name Description indicates complex AC YIELD Active yield flag at integration points Point loads at nodes Logarithmic strain components at integration points Plastic strain components at integration points Equivalent plastic strain at integration points Magnitude of plastic strain at integration points Reaction force at nodes Stress components at integraton points Spatial displacement at nodes Component 1 A D E D D e i D i l n G m G o G m G o G m G n G m G n G a G a G a A a I PREP R 1ciWbir ob UT Ha bore Oe OL bo UT EJ LO h Ca 7 0 0000 LD D O LT UT U Gh h OO ut J Bh e N O EJ bd bJ bJ bJ uJ oJ oJ J d d at ot Our interest now is in the full deflected profile To obtain this in
3. Distribution Direct specification Section variation Constant through solid region Magnitude 293 Note This section variation should only be used with solid sections G MODULE gt MESH a To seed the part instance a Element Shape 1 From the main menu bar select Seed Instance Hexdominsted Tet Wedge 2 Apply 0 0005 for the Approximate global size ee Bit l l F Minimize the mesh transition Tip b To assign mesh controls atructurec Advancing front oe Fig Gl 1 From the main menu bar select Mesh Controls Kae Redefine Sweep Path 2 The Mesh Controls dialog box appears follow the settings depicted in Fig G1 c To assign element type Element Library Family a Standard A Explici t ee el a EIL ee age MO Gaskel From the main menu bar select a Geometric Order ech i a Piezoelectric Mesh gt Element Type Linear ho Quadratic Dare Flos Strece 2 The Element Type dialog box appears Fig G2 Element Controls under the Family list choose Heat transfer Convection Diffusion E Dispersion control The type of element assigned is DC3D8 DC3D8 An amp node linear heat transfer brick d To mesh the part instance 1 From the main menu bar select Mesh gt Instance 2 The generated mesh should resemble Fig G3 Module 2 H MODULE gt JOB 1 From the main menu bar select Job Create 2 Enter Job 3D F
4. Interaction gt Manager to bring up the Interaction Manager dialogue box Fig E7 Click on the box that corresponds to INTER H and Step 3 then click on Deactivate Repeat for INTER V 8 Module 4 F MODULE gt LOAD a To create the boundary conditions e We will create 5 boundary conditions BCs the end result 1s shown in Fig F1 Four of which are displacement boundary conditions Disp BC and the last is a temperature boundary condition Temp BC Note that not all BCs are active at all times A Boundary Condition Manager Name iti Step 1 Step 2 Step 3 Step 4 lt Disp BC 1 Propagated Propagated Propagated Disp BC 2 Created Propagated Propagated Propagated w Disp BC 3 Created Inactive Inactive Inactive Fig F1 w Disp ait Created Propagated Propagated v Temp BC 1 Created Propagated Propagated Propagated Step procedure Coupled temp displacement Boundary condition type Displacerment Rotation Boundary condition status Created in this step 1 Disp BC 1 1 From the main menu bar select BC gt Create E Create Boundary Condition Name Disp BC 1 2 Name it Disp BC 1 Fig F2 Assign to Step Step 1 Step Step 1 Fig F2 Procedure Coupled temp displacernent Category Mechanical Displacement Rotation Category Types for Selected Step Mechanical Symmetry Antisymmetry Encastre 3 Pick RP the reference point of the die Other Displacement Rotation Velocity Anqgular vel
5. Deformed Variable Output Variable C List only variables with results a Description indicates complex Point loads at nodes Point moments at nodes Reaction force at nodes Reaction moment at nodes Spatial displacement at nodes Rotational displacement at nodes Invariant Component Magnitude 22 Module 1 The deformed cantilever beam will now be displayed and coloured according to the contours of displacement From the contours you should be able to see that at the free end the beam has deflected by 11 7 mm Fig 13 AF I IL ELILLELEILILLEILLEILI m G mn A m G ma G a G ma G o G a G m G an G an G a G a Bi bJ u d a a at pe 2 a a _3 3 5 T 7 sd i 2 al Re 0 0 1 h Re a bd e J IN OBI OBI LL eT H 00 ot J Bh RL mowi Our interest now is in the full deflected profile We d like to compare the FEM predicted deflections with those from ordinary beam bending theory To obtain the full FEM predicted profile 4 From the main menu bar select Plot gt Contours gt On Undeformed Shape 5 From the main menu bar select Tools Path Create BH Create Path The Create Path Dialogue box will open Fig 14 E a Name the path Cantilever Path Type Node list b Select Edge List as the Type Point list Edge list C Click Continue Circular The Edit Edge List Path dialogue box will open Fig 15 _Continue a Selec
6. beam material properties E G and v and you will assign these material properties to the beam 1 From the main menu bar select Section gt Create The Create Section Dialogue box will open as shown in Fig B1 Name the W Create Section section Cantilever Section cantilever section Category a Under Category choose Beam solid C Shell Truss b Under Type choose Beam Fig B1 Continue Cancel c Click Continue 2 The Edit Beam Section dialogue box will open Fig B2 Next to Profile Name click Create and the Create Profile dialogue box will open Fig B3 Name the profile Cantilever Profile Select Rectangular and click Continue The Edit Profile dialogue box will open Fig B4 Enter the cantilever cross sectional dimensions a b 0 025 m and click OK 3 In the Edit Beam Section dialogue box next to Material name click Create and the Edit Material Dialogue box will open Fig B5 Name the material Aluminium and then Click Mechanical Elasticity gt Elastic Specify the elastic material properties E and v and click OK Specify the section Poisson s ratio to be 0 33 in the Edit Beam Section dialogue box Click OK E Edit Beam Section Edit Profile Mi Create Profile X Name Cantilever Section _ Type Beam a d Shape Rectangular i Mame Cantilever Profile Profile name Cantilever Profile ka Profile shape Rectangular Basic Stiffness Fluid Inertia i Materi
7. boundary conditions and predefined fields become active by default You can use the Amplitude toolset to specify complicated time or frequency dependencies that can be applied to prescribed conditions The Set and Surface toolsets in the Load module allow you to define and name regions of your model to which you would like to apply prescribed conditions The Analytical Field toolset and the Discrete Field toolset allow you to create fields that you can use to define spatially varying parameters for selected prescribed conditions Load cases are sets of loads and boundary conditions used to define a particular loading condition You can create load cases in static perturbation and steady state dynamic direct steps Figure 5 Assembly of part instances with applied boundary conditions Mesh The Mesh module allows you to generate meshes on parts and assemblies created within Abaqus CAE Various levels of automation and control are available so that you can create a mesh that meets the needs of your analysis As with creating parts and assemblies the process of assigning mesh attributes to the model such as seeds mesh techniques and element types is feature based As a result you can modify the parameters that define a part or an assembly and the mesh attributes that you specified within the Mesh module are regenerated automatically The Mesh module provides the following features e Tools for prescribing mesh density at local and
8. 0 05 0 0 2 04 06 08 1 x Position m 11 Note that in this plot the FEM predicted deflection at the end of the bar is 15 5 mm Ordinary beam bending theory predicts the deflection to be 11 7 mm There is therefore an apparent error of 24 5 Why might this be 35 Module 1 Solution c e Return to the Mesh module and re seed the 3 D beam 200 seeds along the long edges and 5 seeds along the short edges e Re mesh the beam Mesh Instance e Re run the analysis Job gt Job Manager gt Submit e Obtain the deflected profile Tools XY Data gt Create The Create XY Data dialogue box will open Select Path e Compare the FEM predictions with those from beam bending theory 0 01 0 01 0 02 0 03 Yerical Displacement m 0 04 Analytical Prediction 3 Dimensional FEM Model 5000 CSDSR Elements 0 05 0 0 2 0 4 0 6 0 8 1 x Position m lt is clear to see from these two analyses that the mesh density is important However there still remains a small discrepancy between the FEM predicted deflection at the end of the cantilever beam and that predicted by ordinary beam bending theory 7 8 36 Module 1 Solution d Yenical Displacement m Return to the Mesh module and change the element type Mesh gt Element Type Select Quadratic from the Geometric Order Choose C3D20R elements Re mesh the beam Mesh Instance Re run the analysis Job gt Job Manager Submi
9. Expansion Under Type choose Isotropic Reference temperature 20 C Expansion Coefficient alpha 8 42x10 K v Mechanical Elastic Under Type choose Isotropic E Create Section Young s Modulus 200x10 Pa Name Section workpiece Poisson s Ratio 0 3 Category Type c To create the sections and assign them to the parts Shell Generalized plane strain l A Beam From the main menu bar select Section Create Other Name it Section workpiece Fig B3 For Category choose Solid and set Type as Homogeneous Continue _ Cancel In the Edit Section dialogue box Fig B4 under B Edit Section Material pick Aluminium Name Seca eneieee Hic Bd Type Solid Homogeneous 15 Now create a section for the die call it Section die Assign the sections to the relevant parts Plane stress strain thickness 1 OR Cancel 80 Module 4 C MODULE gt ASSEMBLY 1 From the main menu bar select Instance gt Create 2 First create an instance of the Die part Under Instance Type make sure to select Independent mesh on instance Toggle off Auto offset from other instances 3 Then create an instance of the Workpiece part also as an independent instance Make sure that Auto offset from other instances is set as off see Fig Cl 4 The complete assembly of the die and workpiece is depicted on the left panel of Fig C1 D MODULE gt STEP Create Instanc
10. Global direction and not in a direction normal to the tangent of Distribution the node cu fo d Click OK Amplitude Ramp Follow nodal rotation Note Force will be applied per node 19 Module 1 It is now necessary to define the constraint boundary conditions i e to fix the opposite end of the beam so that it cannot move 3 From the main menu bar select BC gt Create The Create Boundary Condition dialogue box will appear Fig F3 W Create Boundary Condition a Name the boundary condition Clamped End Name RTS Step Load Step w Procedure Static General b Choose Load Step for the Step type i Category Types for Selected Step C Choose Mechanical for the Category Mechanical Other Displacement Rotation d Choose Symmetry Antisymmetry Encastre Mek tyka vy Connector displacement for the Types for Selected Step option Connector velocity e Click Continue f Use the mouse cursor to select the first vertex node which is going to be clamped Continue 9 Click Done in the prompt area The Edit Boundary Condition dialogue box will open as seen in Fig F4 a Select Encastre as the boundary condition me Edit Boundary Condition Name Clamped End b Click OK Type Symmetry Antsymmetry Encastre Step Load Step Static General Region Picked XSYMM U1 UR2 UR3 0 YSYMM U2 UR 1 UR3 0 Z5YMM
11. a loading boundary condition You have meshed the instance with 20 two node linear B21 beam elements All that is now required is for the job to be submitted to the solver H MODULE JOB In this module you will submit the job to the solver for analysis 1 From the main menu bar select Job gt Create The Create Job dialogue box will open a Name the job Cantilever_1D b Click Continue 2 The Edit Job dialogue box will open a In the Description Field type 1D Cantilever Beam Bending b Click OK 21 Module 1 3 From the main menu bar select Job gt Submit and choose the Cantilever_1D job 4 You can monitor the job progress by selecting Job Monitor from the main menu bar When the job is complete you can view the results in the visualisation module I MODULE VISUALISATION In this module you can view the results of your analysis output xy data operate on data and export images and movies 1 From the main menu bar select File gt Open Cantilever_1D odb C Temp directory 2 From the main menu bar select Results Field Output The Field Output dialogue box will appear as shown in Fig I1 a From the Output Variables list select U displacement b Under Component select U2 vertical displacements c Click OK 3 From the main menu bar select Plot Contours Deformed Shape MS Field Output Step Frame Step 1 Load Step Frame 1 Step Frame Primary Variable
12. angle measures Therefore the units chosen must be self consistent which means that derived units of the chosen system can be expressed in terms of the fundamental units without conversion factors International System of units SI The International System of units SI is an example of a self consistent set of units The fundamental units in the SI system are length in meters m mass in kilograms kg time in seconds s temperature in degrees Kelvin K and electric current in Amperes A The units of secondary or derived quantities are based on these fundamental units An example of a derived unit is the unit of force A unit of force in the SI system is called a Newton N 1 Newton 1 kg ms Similarly a unit of electrical charge in the SI system is called a Coulomb C 1 Coulomb 1As Another example is the unit of energy called a Joule J 1Joule 1Nm 1A Volt s 1kgm s The unit of electrical potential in the SI system is the Volt which is chosen such that 1 Joule 1 Volt C 1VoltAs Sometimes the standard units are not convenient to work with For example Young s modulus is frequently specified in terms of Mega Pascals MPa or equivalently N mm where 1 Pascal 1 N m In this case the fundamental units could be tonnes 1 tonne 1000 kilograms millimeters and seconds Three sets of consistent units can be found at the back of this handout Rotation and angle measures In Abagus rotational degrees
13. can be assumed as an isothermal rigid body During the extrusion process the bar is forced downwards by 250 mm at a constant displacement rate of 25 mm s The generation of heat attributable to plastic dissipation inside the bar and the frictional heat generation at the die workpiece interface causes temperature of the workpiece to rise When extrusion is completed the workpiece is allowed to cool in the ambient air The ambient surrounding is at 20 C with a coefficient of heat transfer of 10 W m K Formulate an axisymmetric FE model to predict 1 the geometry of the deformed bar 11 the plastic strain distribution and 111 the temperature evolution at various stages of the extrusion process Axis of symmetry Aluminium workpiece 590 mm 19 Module 4 SOLUTION e Start ABAQUS CAE At the Start Session dialog box click Create Model Database e From the main menu bar select Model gt Create The Edit Model Attributes dialog box appears name the model TM_Coupled A MODULE gt PART We will construct an axisymmetric model consisting of a aa ie E Create Part deformable workpiece and a rigid die Name Workpiece Modeling Space a To sketch the aluminium alloy workpiece 3D 2D Planar Axisymmetric 1 From the main menu bar select Part gt Create Type Options 2 Name the part Workpiece Use the settings are shown in Deformable Fig A1 Ensure that the Modeling Space is set to Discrete rigid Indha
14. global levels e Model coloring that indicates the meshing technique assigned to each region in the model e A variety of mesh controls such as 10 e Element shape e Meshing technique e Meshing algorithm e Adaptive re meshing rules A tool for assigning Abaqus Standard and Abaqus Explicit element types to mesh elements The elements can belong either to a model that you created or to an orphan mesh A tool for verifying mesh quality Tools for refining the mesh and for improving the mesh quality Tools for saving the meshed assembly or selected part instances as an orphan mesh part Figure 6 Finite element mesh 11 Element Types The Mesh module can generate meshes containing the element shapes shown on page 22 Most elements in Abaqus Standard and Abaqus Explicit correspond to one of the shapes shown that is they are topologically equivalent to these shapes For example although the elements CPE4 CAX4R and S4R are used for stress analysis DC2D4 is used for heat transfer analysis and AC2D4 is used for acoustic analysis all five elements are topologically equivalent to a linear quadrilateral Every mesh region has one or more Abaqus element types assigned to it by default Each element type corresponds to an element shape that can be used in the region For example a shell mesh region typically has a quadrilateral and a triangular element type assigned to it by default However you can change the element assign
15. menu bar select Mesh Mesh Instance Select the workpiece instance to Defaults Cancel generate the mesh it should resemble Fig G4 a Element Type xs Element Library Family Standard Explicit Cohesive A Geometric Order Gasket Linear Quadratic Heat Transfer Quad Tri e Element Controls Fig G3 Hybrid formulation Reduced integration Hourglass stiffness Second order accuracy Distortion control 30 seeds Hourglass control 1 CAX4T A4 node axisymmetric thermally coupled quadrilateral bilinear displacement and temperature Note To select an element shape for meshing select Mesh gt Controls from the main menu bar OK Defaults Cancel Module 4 b To mesh the die 1 Now hide the workpiece and make the die instance visible 2 Seed the edges of the die as shown in Fig G5 Note To reduce computation time we apply relatively coarse mesh for the die since it acts as a rigid body here and heat transfer across the interface is not accounted for in this analysis 3 Under Mesh Control choose Quad Structured and toggle on Minimize the mesh transition Fig G2 4 Apply CAX4T element type 5 The generated mesh of the assembly is shown in Fig G6 H MODULE gt JOB 1 From the main menu bar select Job Create 2 Enter Job Extrusion as the job name 3 Submit the job and monitor the progress This analysis can take between 15 and 3
16. mm Click OK ki Category Type Solid Homogeneous 4 From the main menu bar select Assign Section Using the Composite Memi mouse cursor click and drag across the plate and click Done in sufa Fig B6 Genelleme the prompt area Click OK in the Edit Section Assignment Continue Cancel dialogue box Click Done in the prompt area W Edit Section Name Plate Section Type Shell Continuum Shell Homogeneous Section integration During analysis Before analysis Basic Advanced Shell thickness Value 0 0004 Distribution Material Weldox 460E ka Thickness integration rule Simpson 2 Gauss Thickness integration points 5 2 ED Fig B7 Whilst in the Property module you must also specify the projectile mass 5 From the main menu bar select Special lnertia gt Create The Create Inertia dialogue box will open Name the mass condition Projectile Mass and select Point Mass as the Type Click Continue Select the Reference Point you created in the Part module as the point to which you wish to assign mass Click Done in the prompt area and the Edit Inertia dialogue box will open Select a mass of 0 002 kg and click OK C MODULE ASSEMBLY 1 From the main menu bar select Instance Create The Create Instance dialogue box will open Select both of the parts and choose Independent as the Instance Type Click OK 2 Translate the projectile in th
17. of the modules follows a logical sequence Abaqus CAE allows you to select any module at any time regardless of the state of your model The available modules in ABAQUS CAE are the part property assembly step interaction load mesh job and visualisation modules Parts You use the Part module to create edit and manage the parts in the current model Abaqus CAE stores each part in the form of an ordered list of features The parameters that define each feature extruded depth hole diameter sweep path etc combine to define the geometry of the part The Part module allows you to do the following e Create deformable discrete rigid analytical rigid or Eulerian parts The part tools also allow you to edit and manipulate the existing parts defined in the current model e Create the features solids shells wires cuts and rounds that define the geometry of the part e Use the Feature Manipulation toolset to edit delete suppress resume and regenerate a part s features e Assign the reference point to a rigid part e Use the Sketcher to create edit and manage the two dimensional sketches that form the profile of a part s features These profiles can be extruded revolved or swept to create part geometry or they can be used directly to form a planar or axisymmetric part e Use the Set toolset the Partition toolset and the Datum toolset These toolsets operate on the part in the current viewport and allow
18. select Interaction gt Create Procedure Coupled temp ee Types for Selected Step 2 Name it CONVECT Select Step 4 and Surface film aT a ara eee Self contact Standard Surface film condition condition see Fig E8 Surface radiation to ambient 3 To pick the surface click on the Surfaces button located at pia a AL MER Concentrated radiation to ambient the right hand corner of the prompt area then select Ssurface workpiece Convect 4 In the Edit Interaction dialogue box enter Film 8 Edit Interaction e o a7 1 e coefficient as 10 W m K and Sink temperature ta Ge as 20 C Type Surface film condition Step Step 4 Coupled temp displacernent E Region Selection Surface Surf workpiece Convect Edit Region Eligible Sets Surfaces below may contain faces Deina Eribedded Coefficient Film coefficient 10 Name Surt die Contact Sun workpiece Convect Surface Film coefficient amplitude Instantaneous I Sink temperature 20 Surt workpiece Horizontal Sink amplitude Instantaneous E Surf workpiece Vertical Highlight selections in viewport Module 4 e Mechanical interactions E Create Interaction 1 From the main menu bar select Interaction gt Create Name INTER H Step Initial 2 Name it INTER H Select Step Initial and Surface to Procedi Types for Selected Step surface contact Standard see Fig E11 re ara Self contact Sta
19. that you created it should be there by default Click OK The part will change colour which is an acknowledgement that that section has been assigned to the material C MODULE gt ASSEMBLY In the assembly module multiple parts can be assembled into an assembly of parts This is done by creating instances of each part In this case we have only one part Cantilever Beam ABAQUS still requires however that an instance of this part is created FYI multiple instances of a single part can be created if required 1 From the main menu bar select Instance gt Create The Create Instance dialogue box will open Fig C1 a Under Instance Type select Independent b Click OK In the step module you will define the type of analysis that is to be undertaken static in this case 1 From the main menu bar select Step Create The Create Step dialogue box will appear Fig D1 Name the step Load GLOP 2 Select General from the Procedure Type options 3 Select Static General from the list of analysis types Click Continue W Create Instance Cantilever Beam Instance Type Dependent mesh on part Note To change a Dependent instance s mesh you must edit its part s mesh C Auto offset from other instances E Create Step Name Load Step Insert new step after Fig D1 Procedure type General Dynamic Explicit Dynamic Temp disp Explicit Geostatic Heat transfer
20. the beam 1 From the main menu bar select Section gt Create The Create Section Dialogue box will open as shown in W Create Section Fig B1 Name the section Cantilever Section Name Cantilever Section Category Type a Under Category choose Solid Solid e b Under Type choose Homogenous Sek Sneraeed pine sirain O Beam c Click Continue Other Fig B1 Continue Cancel 2 The Edit Section dialogue box will open Fig B2 Click Create and the Create Material dialogue box will open Fig B3 Name the material Aluminium Enter a Young s Modulus of E 70 GPa and a Poisson s ratio of v 0 33 and click OK ER Edit Section Ei Edit Material Name Cantilever Section We Ah Type z l Solid Homogeneous Material Bohavur Plane stress strain thickness i General Mechanical Thermal Other i Elastic C Use temperature dependent data Number of field variables Moduli time scale for viscoelastidty Long term C No compression C No tension Data Cancel 27 Module 1 You now need to assign the Cantilever Section and the Cantilever Material to the 3 D beam part that you have created 3 From the main menu bar select Assign Section Using the mouse cursor select the part in the Viewer and click Done The Edit Section Assignment dialogue box will open Check that the Section that is chosen is the Cantilever Section
21. the main menu bar select Load gt Create Name Apply Heatflux Step Transient heating 2 Name it Apply_Heat flux Under Types for Selected Procedure Heat transfer Categor T for Selected St Step choose Surface heat flux see Fig F1 ai eS a Thermal Body heat flux 3 When prompted to choose the surface for the surface heat A Concentrated heat flux Fluid Electrical the bottom surface of the heat sink can be selected Ss Fig F1 Fig F2 flux it would be necessary to rotate the view so that Mame Apply_Heatflux Type Surface heat flux Step Transient heating Heat transfer Region Picked Distribution Uniform Magnitude 100 Amplitude Instantaneous 4 Fill out the Edit Load dialog box as in Fig F3 E Create Field b To create field i e initial temperature Name OMETE Step Initial Procedure 1 From the main menu bar select Predefined Field Create Category Types for Selected Step 2 Name it Initial Temperature Under Step choose Mechanical Initial Under Category choose Other gt Temperature Ss sain see Fig F4 Fig F4 Continue Module 2 3 When prompted to select region for the field drag a i Name Initial Temperature box across the whole assembly to select all surfaces Te eee Step nitial Fi 5 Fill out the Edit Filed dialogue box as in Fig F5 a Region Picked
22. you to create sets partitions and datum geometry respectively Figure 2 Component parts in the indentation model Property e Define materials e Define beam section profiles e Define sections e Assign sections orientations normals and tangents to parts e Define composite layups e Define skin reinforcement e Define inertia point mass rotary inertia and heat capacitance on a part Define springs and dashpots between two points or between a point and ground Material Models You can define a number of different material behaviours in the Abaqus material editor from simple elastic material behaviour to more complicated highly non linear constitutive behaviour Material behaviors fall into the following general categories general properties material damping density thermal expansion elastic mechanical properties inelastic mechanical properties thermal properties acoustic properties hydrostatic fluid properties equations of state mass diffusion properties electrical properties pore fluid flow properties Edit Material Name Copper Description Material Behaviors Elastic General Mechanical Thermal Electrical Magnetic Other Plastic Hardening Isotropic el O Use strain rate dependent data E Use temperature dependent data Number of field variables 0 m gt eo N mao mw hw ee Figure 3 Material editor in Abaqus The material library in Abaqus is i
23. 0 minutes depending on your system 4 When the job is completed from the Job Manager dialogue box click on Results Module 4 I MODULE gt VISUALIZATION 1 To display the deformed configuration after St ep 2 of the analysis Fig 11 from the main menu bar select Plot gt Deformed Shape then use the control buttons in the context bar to scroll through the ODB frames 2 To display plastic strain contours at the end of Step 2 select Result Field Output select PEEQ and use the Step Frame button at the top of the dialogue box to choose the step name Fig I2 3 To show the temperature field at the end of Step 2 select NT11 in ee Result gt Field Output the result is shown in Fig I3 a CELE 13h O71le 02 866e 00 017e 02 750e 00 ss20eTUL 634e 00 sO9LetOlL 517e 00 552e 01 401e 00 O13e 01 284e 00 475e 01 NN a ae Ee BI ee a 1 t EH ee 168e 00 051e 00 35308 01 186e 01 021e 01 893 76 01 692e 01 wees UL 364e 01 199 01 9026 03 4 To generate a 3 D view of the axisymmetric model from the main menu bar select View gt ODB Display Option then click on the Sweep amp Extrude tab toggle on Sweep elements enter the angles and segment specification An example is depicted in Fig I4 with angles from 0 to 270 936e 01 39 cers 858e 01 col Ver cf SLerUL 242e 01 fU Ser UL 164e 01 O2 VETUL 08 7e Ll 07 1e 0z O16e 02
24. 0 seeds using the Seed Edge by Number option 3 From the main menu bar select Mesh gt Element Type Click and drag the mouse cursor over the plate and click Done in the prompt area The Element Type dialogue box will open Select Explicit from the Element Library and Shell from the Element Family options Choose Quad elements and click OK to choose the S4R element type Click Done in the prompt area 4 From the main menu bar select Mesh lInstance Using the mouse cursor select the plate and click Done in the prompt area There is no time during the session today to conduct a mesh sensitivity analysis However you should bear in mind that for simulations of this type the results can be very sensitive to your choice of mesh Under normal circumstances you MUST conduct a sensitivity analysis G MODULE JOB 1 Create a job titled WeldoxBL and submit the job for analysis The job should take approximately one to two minutes H MODULE VISUALISATION 1 From the main menu bar select Results Field Output From the Field Output dialogue box select Mises Stress Make a note of whether or not the plate has fully perforated i e Fig H1 If not increase the impact velocity in the Load module If it has decrease the impact velocity in the Load module Continue to do this until you converge upon the ballistic limit 2 The projectile velocity data can be found from the History Output options accessible from the main menu bar Using this
25. 3 Pick the RP on the die see Fig F7 4 Set the Magnitude as 20 C The temperature of the die remains constant throughout simulation since we are not accounting for heat transfer into the die b To create a thermal field for the workpiece 1 From the main menu bar select Predefined Field Create 2 Name it Field workpiece Assign to Step Initial Category Other gt Temperature 3 Pick the Workpiece instance In the Edit Field dialogue box enter 20 C as the Magnitude This is the initial temperature the temperature in subsequent steps will be computed 90 Module 4 G MODULE gt MESH a To mesh the workpiece 1 First hide the die in the viewport From the main menu bar select Interaction gt Assembly Display Options Instance toggle off the die instance 2 From the main menu bar select Sed gt Edge By Number 3 Assign 10 seeds to the horizontal edge and 30 seeds to the vertical edge see Fig G1 4 From the main menu bar select Mesh gt Controls Use Quad elements and apply Structured green technique Fig G2 5 From the main menu bar select Mesh gt Element E Mesh Controls Type Element Library Standard Under Element Shape Family choose Coupled Temperature eet ne Fig G2 g Technique Algorithm Options Displacement Use element type CAX4T see Fig G3 Fe M Structured E L Redefine Region Cor NETS 7 Minimize the mesh transition Tip 6 From the main
26. 619e 01 075e 01 930e 01 oS 6e 01 442e 01 998e 01 354e 01 o09e 01 63e 01 7 le 0l 177e 01 633e 01 O088e O01 544e 01 000e 01 Module 4 Optional questions l Explore the sensitivity of the model predictions towards the choice of element types and meshing strategies Show how you can monitor and record the temperature history at a specific node located in the vicinity of the hot zone where the maximum temperature is over 100 C see Fig I3 Show how you can model the effects of heat transfer from the workpiece into the die If you re interested in studying the effects of strain rates what extra information will be needed Investigate the contribution of heat generation due to friction towards the overall temperature rise 94 Dimensions and Units for Finite Element Analyses PolymerFEM com Tutorial Background Finite element programs do not consider the units of given quantities it is the user s responsibility to ensure that the given numbers have consistent units There are numerous different sets of units that can be used when performing FE simulations The best set of units will depend on the problem typically the most accurate results are obtained if the units are chosen such that the values of the input quantities to the FE simulation are close to unity By having the input quantities close to 1 the influence of round off errors and truncation errors are reduced Case 1 SI u
27. A is the yield stress under quasi static conditions B and n are strain hardening parameters m controls the temperature dependence and C the strain rate dependence 64 Module 3 a Build a 3 dimensional FE model Since the plates are so thin assume their geometry can be represented by a shell with an 80 mm diameter Assume also that the projectile does not deform either elastically or plastically Beyond the elastic limit the strain hardening behaviour of the plate is best described using the Johnson and Cook constitutive plasticity model Eq 1 recall that this equation neglects any strain rate hardening contribution Fracture in the plates will be modelled using a very simple critical plastic strain fracture criterion The Johnson and Cook material property data for Weldox 460E steel are given in Table I Using this information determine the ballistic limit of the steel plates when struck normal to their plane using a measured quasi static uniaxial plastic fracture strain of 0 33 Predict also the energy absorbed by the steel plates for 5 impact speeds between the ballistic limit and 600 m s when struck normal to their plane b Strain rate hardening effects were neglected in a However the steel plates are known to exhibit rate hardening behaviour Fortunately the Johnson and Cook plasticity model can be modified to include the effects of strain rate hardening Eq 2 Modify your existing material model to include the
28. BAQUS 2 When it comes to meshing there are many possibilities in terms of the choice of mesh size and density element type shape and order and meshing technique or algorithm Explore how some of the above can affect the accuracy of your model predictions 3 Compare the variation of thermal gradients across the different sections of the walls e g along the horizontal vertical diagonal directions etc 52 Module 2 B Three Dimensional Transient Problem Heat Dissipation through Ribbed Surfaces Problem Description Ribbed surfaces or fins are commonly used in engineering applications to dissipate heat The figure below shows the 2 D cross section and 3 D geometry of an aluminium heat sink designed for cooling a microprocessor The thermal conductivity of aluminium is k 170 W m K The initial temperature of the heat sink is 293 K When the microprocessor is operating the bottom surface of the heat sink is exposed to a constant heat flux of q 1000 W m Forced air flow from a cooling fan over the developed surface maintains the surrounding surface at 323 K The convective heat transfer coefficient between the fin and the ambient surrounding is at h 80 Wm K Formulate a transient 3 D FE model to predict 1 the time needed for the heat sink to achieve steady state conditions and 11 the temperature distribution within the developed surfaces 93 Module 2 SOLUTION e Start ABAQUS CAE At the Start
29. Done in the prompt area Repeat the operation for the side edges choosing 80 seeds along each edge as seen in Fig G2 3 From the main menu bar select Mesh gt Element Type The Element Type dialogue box will appear a Choose Standard from the Element Library b Choose Linear for the Geometric Order c Choose 3D Stress for the Family d Click OK to choose C3D8R elements 4 From the main menu select Mesh lInstance 5 Click Yes in the prompt area to generate 320 elements on your part instance Fig G3 Ei Why might having only 2 elements through the thickness of this beam not be a good idea when using linear elements Consult section 4 1 of the ABAQUS user manual 31 Module 1 H MODULE JOB 1 From the main menu bar select Job gt Create The Create Job dialogue box will open as seen in Fig H1 E Create Job a Name the job Cantilever_3D b Select the Cantilever_3D Model Source Cantilever_ 30 c Click Continue 2 The Edit Job dialogue box will open a In the Description field type 3D Cantilever Bending Analysis Continue Cancel b Click OK 3 From the main menu bar select Job gt Submit gt Cantilever_3D You can monitor the progress of your job by selecting Job gt Job Manager from the main menu bar and Monitor from the Job Manager dialogue box The analysis will take approximately 30 seconds although this will depend on the CPU spec
30. II Natural Sciences Tripos Part II MATERIALS SCIENCE FEM Practical Booklet Dr J Dean Lent 2014 15 UNIVERSITY OF CAMBRIDGE Department of Materials Bronze Award Science and Metallurgy Contents Introduction to ABAQUS Abaqus CAE is a complete modelling environment that provides a simple consistent interface for creating submitting monitoring and evaluating results from Abaqus Standard and Abaqus Explicit simulations Abaqus CAE is divided into modules where each module defines a logical aspect of the modeling process for example defining the geometry defining material properties and generating a mesh As you move from module to module you build the model from which Abaqus CAE generates an input file that you submit to the Abaqus Standard or Abaqus Explicit analysis product The analysis product performs the analysis sends information to Abaqus CAE to allow you to monitor the progress of the job and generates an output database Finally you use the Visualization module of Abaqus CAE to read the output database and view the results of your analysis This lecture includes a general introduction to the ABAQUS Graphical User Interface GUI an introduction to model formulation and the concept of Modules discretisation and meshing techniques boundary condition specification job submission results visualisation and analysis checks convergence etc These features will be demonstrated using a finite
31. Johnson and Cook strain rate hardening parameters Table I and the strain rate dependent fracture behaviour Table Il Re run your simulations and predict new ballistic limit and the absorbed energy as a function of the impact speed once more Compare these predictions with those from a Comment on the significance of strain rate hardening in this particular steel alloy c OPTIONAL Determine the ballistic limit of the steel plates when impacted at 45 Use the fully coupled form of the Johnson and Cook equation 65 Module 3 Table A Mpa 310 Table II Strain Rate st 0 01 0 1 1 10 100 1000 10000 Table Ill Density P kg m 7800 Johnson and Cook Material Property Data Mpa 1000 Material Property Data 0 65 1 Rate dependent Fracture Data Stress Triaxiality 0 33 0 33 0 33 0 33 0 33 0 33 0 33 Fracture Strain 0 33 0 32 0 31 0 30 0 29 0 28 0 27 Elastic Constants E GPa 200 V 0 33 T met K 1673 Tiran 293 0 07 Ref Strain rate 1 S 0 01 66 Module 3 Solution a e Start ABAQUS CAE At the Start Session dialogue box click Create Model Database e From the main menu bar select Model gt Create The Edit Model Attributes dialogue box appears name the model Plate Perforation A MODULE gt PART Under the Part module we will construct the plate and projectile me Create Part Name Steel Plate 1 From the main me
32. Mass diffusion Soils Static Riks k 28 Module 1 E MODULE gt INTERACTION There are no interactions in this analysis F MODULE LOAD In the load module you define the boundary conditions constraints and loads You will constrain one end of the cantilever beam to be fixed zero displacements and you will define an 80 N load at the free end of the beam 1 From the main menu bar select Load Create The Create Load Dialogue box will open Fig F1 a Name the load Concentrated Load b Choose Load Step as the Step option c Choose Mechanical for the Category d Choose Concentrated Force for the Type e Click Continue Using the mouse cursor select the two nodes as shown in Fig F2 g Click Done in the prompt area and the Edit Load dialogue box will open Fig F3 h Type 0 for CF1 and CF3 Type 40 for CF2 i e 40 N load at each node MS Edit Load Name Concentrated Load Type Concentrated Force Step Load Step Static General Region Picked csvs Global GR j CEZ Pa E Create Load Name Concentrated Load Step Load Step wt Procedure Static General Category Mechanical Electrical anette Click OK Follow nodal rotation Note Force will be applied per node Types for Selected Step a Moment Pressure Shell edge load Surface traction Pipe pressure Body force Line loa
33. Now create surface film condition for the brick walls that are in contact with the ambient air name it Int OuterWalls Apply it to the surface called Brick outside Enter 0 068 W m K as the Film coefficient and 293 K as the Sink temperature E Create Interaction i E Edit Interaction Name Int InnerWallg Name Int InnerWalls Step Heatin Jr Fig E2 Type Surface film condition Fig E3 Step Heating Heat transfer Procedure Heat transfer Types for Selected Step Surface Concrete inside Surface to surface contact Standard Definition Embedded Coefficient Self contact Standard Surface film condition Surface radiation to ambient Film coefficient amplitude Instantaneous Concentrated film condition Film coefficient 0 01 Concentrated radiation to ambient sink temperature 12 3 Sink amplitude Ramp A Continue l OK Cancel Module 2 F MODULE gt MESH a To seed the part instance 1 From the main menu bar select Seed Instance 2 Left click on the Brick region click Done in prompt area The Global Seeds dialog box appears enter 0 1 for Approximate global size accept the rest of the settings and click OK 3 By following the above steps now apply an Approximate global seed size of 0 02 to the Concrete region a Mesh Controls b To assign mesh controls Element Shape 1 From the main menu bar select Mesh gt Controls Technique Algorithm 2 Se
34. Session dialog box click Create Model Database e From the main menu bar select Model gt Create The Edit Model Attributes dialog box appears name the model 3D_Fin A MODULE gt PART l 2 From the main menu bar select Part Create Name the part Fin and follow the settings depicted in Fig Al The approximate size is set at 0 1 metre Sketch the 2 D profile Fig A2 according to the dimensions given in the Problem Description Note Remember to construct the model in SI units Tips a To ease sketching click on the Sketcher Options located in the Sketcher toolbox and change the tool Grid spacing to 0 001 and the Minor Intervals to 1 b You can exploit the symmetry by using the Mirror tool located under Edit gt Transform Mirror When done sketching click Done in the prompt area The Edit Base Extrusion dialog box appears enter the base extrusion depth as 0 02 0 0040 gt jns 0 0010 E Create Part Mame Fin Modeling Space 5D 2D Planar Axisymimetric Type Options Deformable None available Discrete rigid Analytical rigid Base Feature Shape Type Shell Revolution i Sweep Wire Point Approximate size 0 1 Continue Cancel 54 Module 2 B MODULE gt PROPERTY 1 From the main menu bar select Material gt Create 1 ee TEN Edit Material 2 Name the material Aluminium AARE Name Aluminium Material Behaviors Conductivity 3 Create the
35. To access the data from the main menu bar select XY Data gt Edit gt Al Deflection Elastic 3D Compare these predictions with those from ordinary beam bending theory 34 Module 1 X m Field Output Step Frame Step 1 Load Step Fame 1 Primary Variable Deformed Variable EE XY Data from Path Data Extraction Path Cantilever Path J Model shape Deformed Undeformed Point Locations Output Variable r _ List only variables with results True distance X distance oe Normalized distance Y distance i C iadicates plex AC YIELD Active yield flag at integration points Sequence ID Z distance CF Point loads at nodes Y Values Logarithmic strain components at integration points Step 1 Load Step PE Plastic strain components at integration points Frame 1 PEEQ Equivalent plastic strain at integration points Field output variable UU2 PEMAG Magnitude of plastic strain at integration points RF Reaction force at nodes Note Result option settings will be applied to calculate result values for the current S Stress components at integration points step and frame U Spatial displacement at nodes Magnitude 0 01 0 02 0 03 vertical Displacement m 0 04 Analytical Prediction 3 Dimensional FEM Model 320 CSDSR Elements
36. U3 UR 1 UR2 0 XASYMM U2 U3 UR 1 0 ABAQUS Standard only YASYMM U1 U3 UR 0 ABAQUS Standard only ZASYMM U1 U2 UR3 0 ABAQUS Standard only PINNED U1 U2 U3 0 G MODULE MESH In this mesh module you will mesh the Cantilever Beam instance by assigning seeds nodal positions mesh controls and element types 1 From the main menu bar select Seed Edges 2 Use the mouse cursor and select the Cantilever Beam instance and click Done in the prompt area 20 Module 1 In the Local Seeds dialogue box that appears change the seeding method to By Number 3 Type 20 for the number of nodes along the beam length 4 Click OK 5 From the main menu bar select Mesh Element Type Using the cursor select the part instance and click Done in the prompt area The Element Type dialogue box will appear as shown in Fig G1 6 Choose Standard from the Element Library 7 Choose Linear for the Geometric Order 8 Choose Beam for the Family 9 Click OK 10 From the main menu bar select Mesh lInstance 11 Click Yes in the prompt area Note To select an element shape for meshing select Mesh gt Controls from the main man menu Der You have so far built the geometry prescribed the beam section geometry the beam material properties and the beam section orientation You have created an instance of the Cantilever Beam part defined a constraint boundary condition and
37. Under Concrete Parts select Brick For Instance Type choose Independent mesh on instance Toggle on Auto offset from other 7 Fig C1 instances Click OK Instance Type 3 Dependent mesh on part 3 Now create an instance for the part Concrete Poe Se Independent mesh on instance 4 At this point before we proceed onto assembling the instances Note To change a Depa mesh you must edit its part s mesh it would be useful to define several sets of surfaces for use in J Auto offset from other instances later stages of the analysis From the main menu bar select Apply Cancer Tools gt Surface gt Create The Create Surface dialog box i appears Name it Brick inside and pick the four edges located inside the Brick instance see Fig C2 Note you may need to press and hold the Shift key to make multiple selections Click Done in the prompt area Repeat to create another set of surface called Brick outside consisting of four edges located outside the Brick instance see Fig C2 5 Now create the following surfaces on the Concrete instance name them Concrete inside and Concrete outside corresponding to the four inner and outer edges of the Concrete instance as depicted in Fig C2 Brick outside 46 Module 2 6 We ll now assemble the two instances From the main menu bar select Instance gt Translate Select the Concrete instance and click Done By picking the suitable s
38. ace constructed from two materials The inner wall is made of concrete with a thermal conductivity of ke 0 01 W m K The outer wall is made of bricks with a thermal conductivity of kp 0 0057 W mt K The temperature in the furnace is at 1273K and the convective heat transfer coefficient is h 0 208 W m K The outer brick wall comes into contact with the ambient air which is at 293 K and the corresponding convective heat transfer coefficient is hy 0 068 W m K Formulate a 2 D FE model and solve for 1 the temperature distribution within the concrete and brick walls at steady state conditions and 11 the heat flux across the walls F b b k t b F b b j j b 3 m 43 Module 2 SOLUTION e Start ABAQUS CAE At the Start Session dialog box click Create Model Database e From the main menu bar select Model gt Create The Edit Model Attributes dialog box appears name the model 2D_Walls A MODULE gt PART Under the Part module we will construct the two parts 1 e walls G Brick and 11 Concrete 1 From the main menu bar select Part gt Create 2 The Create Part dialog box appears Name the part Brick and fill in the rest of the options as in Fig Al Click Continue to create the part E Create Part 3 There are several ways of constructing the brick wall geometry i Name Brick One way to do this is demonstrated here 3 7 Modeling Space a From the Sketcher toolbox select th
39. aded at its end with a force of 80 N Compare the FEM predicted deflections with those predicted by ordinary beam bending theory Assume that the beam is made from aluminium is homogenous and isotropic and that it behaves in a linear elastic fashion c Using the 3 dimensional FE model investigate the effect of mesh density on the predicted FEM deflections Re mesh the cantilever beam with 5000 C3D8R elements and re run the analysis Compare the subsequent FEM predicted deflections with those of ordinary beam bending theory d Investigate the effect of element type on the predicted FEM deflections Re mesh the cantilever beam with 5000 C3D20R elements and re run the analysis Compare the subsequent FEM predicted deflections with those of ordinary beam bending theory Why might these elements be more accurate e Using the 3 D FE model 5000 C3D20R elements plot the distribution of stress through the section of the model at x 0 7 f Compare the predicted stress at x 0 1 for y 0 004 and y 0 0125 where y is the distance from the neutral axis with the stress at those positions predicted by ordinary beam bending theory Plot these predictions on the same graph 15 Module 1 Solution a e Start ABAQUS CAE At the Start Session dialogue box click Create Model Database with Standard Explicit Model e From the main menu bar select Model gt Create The Edit Model Attributes dialogue box appears name the m
40. al name Aluminium ka Section Poisson s ratio Temperature variation Linear by gradients Hexagonal Interpolated from temperature points Trapezoidal Name Cantilever Profile Rectangular E Edit Material I Name Aluminium L Description E F ig E B 2 T F Ig e B 3 banin Behaviors Arbitrary Generalized a a General Mechanical Thermal Other Elastic i Continue os Cancel Type Isotropic v C Use temperature dependent data Number of field variables O Moduli time scale for viscoelasticity Long term v C No compression C No tension Cancel e p Young s Poisson s F l g B 5 Modulus Ratio 1 70e9 0 33 17 Module 1 4 From the main menu bar select Assign Section Use the mouse cursor to select the Cantilever Beam part and select Done in the prompt area The Edit Section Assignments dialogue box will open as shown in Fig B6 a Check that Cantilever Section Is E Edit Section Assignment selected under the Section options Ce b Check that the Type is Beam Note List contains only sections applicable to the selected regions Type Beam c Click OK Material None It is now necessary to define a beam orientation this is oa Fig B6 important for the second moment of area N calculation Ree ae particularly if the beam has geometry where a b In this case a b and the moment of area is independen
41. ar select Output gt History Output Request gt Create gt H Output 1 3 The Edit History Output Request dialogue box appears Fig D4 Change the Domain to Set and choose Set Nodel Save output at Every 1 Name H utput 1 Step Transient heating increments Under Output Variables choose Procedure Heat transfer Domain Set x Set Nodel Thermal NT Nodal temperature Son cote a E N RET Output Variables Select from list below Preselected defaults All Edit variables d Create a DOF monitor NT gt E Displacement Velocity Acceleration 1 A Degree of Freedom DOF monitor is useful to gt E Energy Y E Thermal follow the progress of a transient analysis Here V NT Nodal temperature _ TEMP Element temperature E FTEMP F we ll set up Set Node1 to monitor the 2g HFLA HFL multiplied by the area temperature evolution Output for rebar 2 From the main menu bar select Output at shell beam and layered section points Use defaults Specify Output gt DOF Monitor 3 Fill out the options as in Fig D5 Note that DOF 11 corresponds to temperature in AB AQUS IC AE Monitor a degree of freedom throughout the analysis Region Set Nodel Degree of freedom 11 Print to the message file every 1 increments 57 Module 2 E MODULE gt INTERACTION 1 From the main menu bar select Interaction7 gt Create E Create Interaction Name Int Convecti 2 Nam
42. ate the following material properties i General gt Density 2700 kg m ii Thermal gt Conductivity e Under Type choose Isotropic e Toggle on Use temperature dependent data NB Conductivity in W m K Temp in C and use data shown in Fig B1 iii Thermal Inelastic Heat Fraction 0 9 iv Thermal gt Specific Heat 880 J kg K v Mechanical Elastic Under Type choose Isotropic Young s Modulus 69x10 Pa Poisson s Ratio 0 33 vi Mechanical gt Expansion Under Type choose Isotropic Reference temperature 20 C Expansion Coeff alpha 8 42x10 K E Edit Material Name Workpiece Aluminium Material Behawiors Density Elastic Fi g B 1 Expansion Inelastic Heat Fraction General Mechanical Thermal Other Conductivity V Use temperature dependent data Number of field variables I Data Conductivity Temp 1 204 0 2 225 300 78 Module 4 vii Mechanical Plasticity Plastic E Edit Material Under Hardening choose Isotropic Fig B2 Name Workpiece Aluminium Behaviors F i g B 2 Elastic Toggle on Use Temperature dependent data The complete set of data is given in Table 1 BAEN l Inelastic Heat Fraction Note The list of data can also be directly serea imported into ABAQUS CAE if an General Mechanical Thermal Other ASCII text file is available VOT Plastic Hardening Isotropic x z Suboptions provided in this exercise To do th
43. b Manager 2 The Job Manager dialog box appears Fig G1 select Job 2D Thermal and click on the Submit button To see the progress of the analysis and to monitor error and warning messages click the Monitor button to bring up the Monitor dialog box Fig G2 E Job Manager Write Input lob 2D Thermal 2D_Walls Full Analysis Co ted lob 2D Therma D Wa ull Analysi omplete Submit Fig Gl Results 3 Create ites z Rename Delete Dismiss c To analyse the results When the job is Completed click E Job 2D Thermal Monitor on the Results button on the Job Job Job 2D Thermal Status Completed Severe 4 z Equil Total Total Step Time LPI Manager dialog box Fig G1 Step increment AN Dixen Her Her TimeyFreg Time iPF inc Iter 1 1 1 0 1 1 1 1 1 J Log Errors Warnings Output Note If the job fails to complete Started Analysis Input File Processor go back to the Monitor dialog Completed Analysis Input File Processor Started ABAQUS Standard box Fig G2 and examine the Completed ABAQUS Standard messages under Errors and Completed Wed Jan 07 12 41 53 2009 Warnings tabs which often will provide clues on how to troubleshoot the analysis 50 Module 2 H MODULE gt VISUALIZATION l 2 From the main menu bar select Results gt Field Output The Field Output dialog box appears under Primary Variable selec
44. cement or coupled thermal electrical step Similarly you can define an interaction with a user defined actuator sensor only during the initial step The Set and Surface toolsets in the Interaction module allow you to define and name regions of your model to which you would like interactions and constraints applied You can use the Amplitude toolset to define variations in some interaction attributes over the course of the analysis The Analytical Field toolset allows you to create analytical fields that you can use to define spatially varying parameters for selected interactions The Reference Point toolset allows you to define reference points that are used in constraints and creating assembly level wire features Abaqus CAE does not recognize mechanical contact between part instances or regions of an assembly unless that contact is specified in the Interaction module the mere physical proximity of two surfaces in an assembly is not enough to indicate any type of interaction between the surfaces Load There are many different load types that you can define in ABAQUS Prescribed conditions in Abaqus CAE are a step dependent object which means that you must specify the analysis steps in which they are active You can use the load boundary condition and predefined field managers to view and manipulate the stepwise history of prescribed conditions You can also use the Step list located in the context bar to specify the steps in which new loads
45. d Gravity Bolt load i Toggle off Follow Nodal Rotation Module 1 2 From the main menu bar select BC gt Create The Create Boundary Condition dialogue box will open as shown in Fig F4 E Create Boundary Condition a Name the boundary condition Clamped End Name efus ee iege b Choose Load Step for the step Tae Procedure Static General Category Types for Selected Step c Choose Mechanical for the Category Mechanical Symmetry Antsymmety Encastre Other Displacement Rotation d Choose Symmetry Antisymmetry Encastre Velocty Anguiar velocity for the Types for Selected Step a e Click Continue f Using the mouse cursor select the opposite end of the bar to which the loading condition was specified Fig F5 The selected face will turn ourple red 3 The Edit Boundary Condition dialogue box will appear a Choose Encastre as the boundary condition b Click OK Le 3 G MODULE gt MESH 1 From the main menu bar select Mesh gt Controls The Mesh Controls dialogue box will appear as shown in Fig G1 E Mesh Controls a Choose Hex as the Element Shape Sega b Select Structured for the Technique Technique C Sweep F 30 Module 1 2 From the main menu bar select Seed Seed Edge by Number Using the mouse cursor holding shift select the end faces Click Done in the prompt area Type 2 for the number of elements along those face edges Click
46. de twist Axisymmetric and the Type as Deformable Anaya 3 Sketch the Workpiece the 4 vertices as shown in Fig A2 Base Feature Shell are 0 0 0 1 0 0 0 3 and 0 1 0 3 in metres w wire Note When building an axisymmetric model it is important Point Fig Al to observe the position of various parts in relation to the axis of symmetry Approximate size 2 Continue Cancel symmetry 0 1 0 3 76 Module 4 b To sketch the rigid die 1 From the main menu bar select Part Create 2 Name the part Die Apart from the name all the other settings are the same as in Fig A1 Note Although the die is meant to be a rigid body in this analysis here we choose to first build it as a deformable body and later apply a Rigid body constraint Section E c 3 Sketch the Die using the vertices given in Fig A3 Note Observe that all coordinates are followed correctly so that the assembly of the workpiece and die can be carried out correctly later 4 We also need to add a reference point to the die part to be used in rigid body constraint From the main menu bar select Tools gt Reference Point Pick point 0 067 0 18 as denoted in Fig A3 note that a yellow RP symbol appears 02 041 0 25 0 41 z 0 25 0 18 ir Module 4 B MODULE gt PROPERTY a To enter material properties of the workpiece 1 From the main menu bar select Material gt Create 2 Name the material Aluminium 3 Cre
47. dule we will construct the beam 3 D 1 From the main menu bar select Part gt Create 2 The Create Part Dialogue box appears Name the part Cantilever Beam and fill in the options as shown in Fig A1 Click Continue to create the part 3 From the main menu bar select Add gt Line gt Rectangle E Create Part cad a Select the co ordinates 0 0 for the first vertex Name Cantilever Beam enter as shown in Fig A2 Modeling Space b Select the co ordinates 1 0 025 for the second 30 20Planar Axisymmetric vertex enter Type Options f or cil c Click x in the prompt area Deformable Discrete rigid None available d Click Done in the prompt area analytical rigid Base Feature Shape Solid oO Shell Revolution SWeep Wire Point Approximate size wl Pick a starting point for the line or enter X Y lo 0 4 The Edit Base Extrusion dialogue box will open In the Depth Field type 0 025 and click OK The part Cantilever Beam will now appear in the Viewer window as a 3 dimensional beam The following tasks must be completed e The beam material properties must be defined e The boundary conditions constraints and loads must be defined e A mesh must be assigned 26 Module 1 B MODULE PROPERTY In this module property you will define the beam material properties E and v and you will assign these material properties to
48. e Workpiece Instance Type Independent mesh on instance Note To change a Dependent instance s mesh you must edit its part s mesh Auto offset from other instances ia This fully coupled thermal displacement transient analysis will consist of an initial step exist by default plus 4 additional steps to be created in this section Fig D1 shows the Step Manager dialogue box with all the steps correctly set up E Step Manager Initial Coupled temp displacement Transient Coupled temp displacement Transient Coupled temp displacermnent Transient Coupled temp displacement Transient Important The Nlgeom option must be enabled to account for large strain plastic deformations 81 Module 4 a To create Step 1 Stabilise workpiece inside die E3 Create Step Name Step 1 1 From the main menu bar select Step gt Create Insert new step after 2 Name it Step 1 Fig D2 The Procedure type is General Coupled temp displacement Fig D2 3 In Edit Step dialog box under the Basic tab Fig D3 enter ae ee Procedure type General Stabilise workpiece inside die as the Description Coupled temp displacement To account for large plastic deformation toggle on Nlgeom To a Dynamic Implicit consider time dependent plasticity toggle on Include Dynamic Explicit Dynamic Ternp d
49. e 1 Click OK Pick this 6 Create a surface called Surf workpiece Vertical 1 e ee the vertical edge that comes into contact with the die see Fig E3 Pick this 7 Create a surface called Surf workpiece Horizontal nae as designated in Fig E3 Pick this 8 Finally create another surface called N Surf workpiece Convect that consists of 3 edges Pick this denoted in Fig E4 9 Toggle on both instances when finished assigning all surfaces Pick this Surf workpiece Vertical a a Pick this 84 Surf workpiece Horizontal gt Pick this Module 4 b To create the interaction property a Edit Contact Property Fi 2 e KS 1 From the main menu bar select Name IntProp 1 Contact Property Options Interaction Property Create Heat Generation 2 Name it IntProp 1 Under Type select Contact 3 Inthe Edit Contact Property dialogue box Fig E5 Tangential Behavior add the following pr operties Friction formulation Penalty gt l TPE Shear Stress Elastic Slip 1 Mechanical gt Tangential Behavior Directionality Isotropic Anisotropic Standard only Use slip rate dependent data For Friction formulation choo se Pen alty Use contact pressure dependent data F Use temperature dependent data Number of field variables 0 e Friction Coeff 0 1 Friction Coeff 0 1 ii Thermal gt Heat Generation e Use 0 5 0 5 Cance
50. e Create Isolated Point 3D 2D Planar Adsymmetiic tool then type in coordinates of the four key vertices ies ia Deformable 0 0 0 9 0 9 2 1 2 1 and 3 3 If not all plotted points recente Fg sc T Spn Analytical rigid are visible press the Auto Fit View button located on Base Feature the toolbar Shell b From the Sketcher toolbox select the Create Lines Wire Point ml Rectangle tool L and connect the inner and outer pairs of Fig Al vertices to form two squares as shown in Fig A2 Approximate size 10 c Click on Done in the prompt area Continue Cancel 2 1 2 1 0 9 0 9 44 Module 2 4 Now construct the second part by following procedures similar to the ones outlined above Name the new part Concrete The four key vertices are 0 0 0 1 0 1 1 1 1 1 and 1 2 1 2 B MODULE gt PROPERTY a To define the materials E Edit Material SA Name Material brick 1 From the main menu bar select Material gt Create Material Behaviors 2 The Edit Material dialog box appears see Fig B1 Name it Material brick Select Thermal Conductivity General Mechanical Thermal Other Delete and enter a value of 0 0057 Condiecmeas Type Isotropic 7 3 Click OK Use temperature dependent data Number of field variables 0 Data Conductivity 1 0 0057 as its thermal conductivity asses a 4 Now create Material concrete Enter a value o
51. e Positive Z direction by 6 mm Instance Translate Click OK in the prompt area 69 Module 3 D MODULE gt STEP 1 From the main menu bar select Step gt Create The Create Step dialogue box will appear Name the step Impact Step 2 Select General from the Procedure Type options 3 Select Dynamic Explicit from the list of analysis types Click Continue The Edit Step dialogue box will open Choose a time period of 0 0002 s 200 us Toggle on NLGEOM Click OK 4 Failed elements will need to be removed from the mesh in order to monitor crack propagation in your analyses In the Field Output Requests toggle on Status which can be found under the State Field User Time options 5 To monitor the projectile velocity create a new History Output Request called Projectile Velocity Choose Projectile Set for the Domain and select V3 from the V options underneath the Displacement Velocity Acceleration list E MODULE gt INTERACTION 1 From the main menu bar select Interaction gt Create The Create Interaction dialogue box will open a Name the interaction Projectile Plate Contact b Choose Surface to Surface for the Types for Selected Step c Click Continue 2 You will be prompted to select the first Master surface Using the mouse cursor select the surface of the analytical rigid projectile and click Done in the prompt area 3 When prompted choose Brown in the prompt area which represents the outer surface o
52. e it Int Convection Under Types for Selected Go lems Step Transient heating Step choose Surface film condition see Fig E1 Procedure Heat transfer Types for Selected Step 3 The next task is to select the surfaces to apply the film Surface to surface contact Standard Self contact Standard Surface film condition involved it will be more convenient to do it as follows Surface radiation to ambient Concentrated film condition conditions However since there are so many surfaces Concentrated radiation to ambient a From the main menu bar select View Toolbars gt Views Continue Cancel 2 b Click the Apply Front View button L c Now drag a box across the screen to pick all surfaces above the base surface as indicated by dotted lines in Fig E2 Important Ensure that all surfaces are selected except the base d The Edit Interaction dialog box appears 8 Edit Interaction Fig E3 fill in the Film coefficient as 80 K Name Int Convection Type Surface film condition and set the Sink temperature as 323 Steg _Trandieni healer pea W m K Surface Picked Define Embedded Coefficient Film coefficient 80 Film coefficient amplitude Instantaneous Sink temperature 323 Sink amplitude Instantaneous 58 Module 2 F MODULE gt LOAD a To create load i e heat flux at the base of heat sink Create Load 1 From
53. efines which variables will be output during an analysis step from which region of the model they will be output and at what rate they will be output See output requests for the model For example you might request output of the entire model s displacement field at the end of a step and also request the history of a reaction force at a restrained point Specify adaptive meshing e You can define adaptive mesh regions and specify controls for adaptive meshing in those regions Specify analysis controls e You can customize general solution controls and solver controls Interaction You can use the Interaction module to define the following Contact interactions Elastic foundations e Cavity radiation e Thermal film conditions e Radiation to and from the ambient environment e Incident waves e Acoustic impedance e Cyclic symmetry e A user defined actuator sensor interaction e Tie constraints e Rigid body constraints e Display body constraints e Coupling constraints e Shell to solid coupling constraints e Embedded region constraints e Equation constraints Connector section assignments Inertia Cracks Springs and dashpots Interactions are a step dependent object which means that when you define them you must indicate in which steps of the analysis they are active For example you can define film and radiation conditions on a surface only during a heat transfer coupled temperature displa
54. el and assuming elastic perfectly plastic behaviour plot the residual curvature of the cantilever beam after it has been loaded at its end with a force of 600 N Compare the deflected profile from Question 1 with this residual curvature Hint Think about creating a second step in which the load from the Load Step is not Propagated 3 Assume now that the aluminium exhibits linear work hardening behaviour with a work hardening rate do de of 300 MPa Compute the deflection of the beam when loaded at its end with a force of 600 N Compute also the deflection of the beam when the load is removed Compare the results with those of the perfectly plastic case Hint Oy 150 MPa at Eplastic 0 and Oy 450 MPa at Eplastic 1 4 Assume now that the aluminium hardens according to a power law relationship of the following n plastic kind 0o 0 ke where the yield stress is 150 MPa kis a constant equal to 300 MPa and the hardening exponent n is 0 4 Calculate o for 0 lt plastic lt 1 Using this data compute the deflection of the cantilever beam loaded at its end with a force of 600 N Find also the residual curvature of the beam Compare these data with the linear work hardening case 42 Module 2 Heat Transfer Analysis Type of solver ABAQUS CAE Standard A Two Dimensional Steady State Problem Heat Transfer through Two Walls Problem Description The figure below depicts the cross sectional view of a furn
55. element model of indentation Fig 1 S Mises mI y Avg 75 eee th i a Avg ULE fh paai finan h mi TH HHA miin uM HI dandanas LTTE tin TH Hl ee Mt i Hh hl li Hl mt i HH ae pini fi lj HT i il Ht yi AREAL HI Mmi ii Ht HH i pn nji Sr HH HM Hy H y STH bth THLE m aaan e it es Hi Men yp p AATE HHH ay H Hata LL ita HIN He Wah fy HTN Willi li Hild Wingy Figure 1 Predicted contours of von Mises stress in a copper specimen indented with a rigid spherical indenter 25 um diameter Components of an Abaqus Model Modules Abaqus CAE is divided into functional units called modules Each module contains only the tools that are relevant to a specific portion of the modeling task For example the Mesh module contains only the tools needed to create the meshes while the Job module contains only the tools used to create edit submit and monitor analysis jobs Abaqus Viewer is a subset of Abaqus CAE that contains only the Visualization module You can select a module from the Module list in the context bar Alternatively you can select a module by switching to the context of a selected object in the Model Tree The order of the modules in the menu and in the Model Tree corresponds to the logical sequence you follow to create a model In many circumstances you must follow this natural progression to complete a modelling task for example you must create parts before you create an assembly Although the order
56. ent Rotation Velocity Angular velocity Acceleration Angular acceleration Connector displacement Connector velocity Connector acceleration Continue Cancel 2 Click Done in the prompt area The Edit Boundary Condition dialogue box will open Select Encastre and click OK Ei Create Predefined Field X 3 Create a further boundary condition that will allow the projectile to Name Projectile Veloctyl move in the Z direction axis 3 only Assign this boundary condition to Step intil the projectile Reference Point that you created earlier Category r Types for Selected Sts Mechanical 4 To define the projectile velocity from the main menu bar select _ Predefined Field Create Select the options shown in Fig F3 for the Create Predefined Field dialogue box Click Continue 5 When prompted to select the region for the Predefined Field select the projectile Reference Point once more Click Done in the prompt area 6 In the Edit Predefined Field dialogue box that appears choose V1 V2 0 and V3 150 Click OK when done 71 Module 3 G MODULE MESH 1 From the main menu bar select Mesh Controls Using the mouse cursor click and drag across the plate remove the projectile using the viewing options a Select Quad as the Element Type b Select Free as the Technique c Select Medial Axis as the Algorithm type d Click OK 2 Using the Seed options seed all 3 edges with 5
57. f 0 01 b To define the sections 1 From the main menu bar select Section gt Create Fig Bl 2 The Create Section dialog box appears Fig B2 Name it Section brick In the Category list accept Solid as Ok E Cancel the default selection In the Type list accept Homogeneous E Create Section as the default selection and click Continue 1 rer Category Type the Material text box and choose Material brick Shell Generalized plane strain Eulerian 3 The section editor appears Fig B3 Click the arrow next to Accept the default value for Plane stress strain thickness Beam 6 Other and click OK Composite Continue 4 Now define Section concrete c To assign a Section to a part 1 From the main menu bar select Assign Section NERS ETE Name Section brick 2 Click on the Brick region and then click Done Type Solid Homogeneous 3 The Edit Section Assignment dialog box appears j bmi E Plane stress strain thickness 1 ok Cancel containing a list of existing sections Click the arrow next to the Section text box and choose Section brick 45 Module 2 and click OK Note the colour of a part becomes aqua when it has been assigned a section 5 Now assign Section concrete to the concrete region C MODULE gt ASSEMBLY 1 From the main menu bar select Instance gt Create me Create cee Parts 2 The Create Instance dialog box appears Fig C1
58. f the projectile 4 You now need to define the second Slave surface involved in the contact Select Surface from the prompt area Using the mouse cursor select the inner partitioned region of the plate Fig E1 Click Done in the prompt area Select Brown when prompted to choose a side for the shell surface 5 The Edit Interaction dialogue box p mum will open Fig E2 From the Z Sconce Discretisation Method select sst 6de m Fig E2 Surface to Surface a o C Exclude shell membrane element thickness 6 Click the Create tab next to Contact Interaction Property The Create Interaction Property dialogue box will open 7 Name it Contact Interaction and select Contact as the Type Click Continue and the Edit Contact Property box will open Select Mechanical gt Normal and accept the default options by clicking OK Click OK again 70 Module 3 F MODULE gt LOAD 1 From the main menu bar select BC gt Create The Create Boundary Condition dialogue box will open Fig F1 a Name the boundary condition Clamp b Choose Mechanical for the category c Choose Symmetry Antisymmetry Encastre for the Types for Selected Step d Click Continue e You must now select the region for the Clamp boundary condition as shown in Fig F2 E Create Boundary Condition Step Impact Step wt Procedure Dynamic Explicit Category Types For Selected Step O Mechanical Symmetry l Antisymmetry i Encastre Other Displacem
59. following material properties Fig B1 Density General Density 2700 kg m PEAR Thermal Conductivity 170 W m K General Mechanical Themmal Other Conductivity Thermal gt Specific Heat 950 J kg K Type Isotropic E Use ternperature dependent data Note Since this will be transient heat transfer h Number of field wariables Data specific heat properties analysis we need to include both density and 4 Create a new Section name it Section Fin use the settings as shown in Fig B2 and Fig B3 5 Assign the section to the Fin part Cancel B Create Section Name Section Fin E Edit Section Category Type Name Section Fin eS Sa Shell Generalized plane strain Materiak Aluminium O Beam A Di Plane stress strain thickness 1 6 Other 1g 8 Continue Cancel C MODULE gt ASSEMBLY 1 From the main menu bar select Instance gt Create 2 Create an instance of the Fin part Under Instance Type make sure to select Independent mesh on instance 55 Module 2 D MODULE gt STEP a To create the transient analysis step l 2 From the main menu bar select Step gt Create Name it Transient heating The Procedure type is General gt Heat Transfer E Edit Step In the Edit step dialog box Name Transient heating Fig D1 under the Basic tab Type Hea eae ensure that the Response 1S i sic i Incrementation Descrip
60. for Traction Separation Lows F Cand pon Plraticlby bain Mumbar of Damaz for Tratin Sepi alian Lares Damaja for Fiera woad Companies F Cli Plasticity H o Damage for Piber thenfonted Composites k Number of Daraga For Platos b Comennghe Darrier Plersticiby Wirt oot a vi Damage for Elashoners k Modit Defrim Pity Coronebe Imesed Credia Defao Pay Elkoro Dempa Crushsble Fosm re Miko tere F apanaian Drucker Prager bki Cracking Mohr Coulomb Flashicity cai Prorat peta Polik Young s Poisson s Creep Misrah Ratin WHOLE e Fig B1 Ca Cancri E Edit Material S Editor Name rate ind Damage Evolution Description Type Displacement Softening liner w Material Behaviors Degradation Maximum amp C Use temperature dependent data Ductile Damage Number of field variables O Damage Evolution Data Density Elastic Displacement at Failure Plastic 1 0 0001 Fig B5 e General Mechanical Thermal Other i Ductile Damage T Use temperature dependent data Fi g B 4 v Suboptions Number of field variables On Data Fracture Strain Stress Triaxiality Strain Rate 1 0 33 0 33 0 01 68 Module 3 2 From the main menu bar select Section gt Create The Create Section dialogue box will open Fill in the Create Section dialogue box as shown in Fig B6 and click Continue 3 The Edit Section dialogue box will appear Fig B7 You must Ml Create Section E now define the thickness of the plate 0 4
61. form gt U1 4 Set U2 0 000125 m v U2 0 000125 Note A relatively small vertical UR3 radians Amplitude Ramp gt displacement is assigned to the top OK Cancel surface of the workpiece at the start of the simulation to establish contacts at the interfaces 5 Deactive this BC for Step 2 and beyond use the Boundary Condition Manager to do this see Fig F 1 89 Module 4 iv Disp BC 4 1 From the main menu bar select Pick this edge BC gt Create 4 a Edit Boundary Condition Name Disp BC 4 PA Name it D 1 S P B C 4 7 Assign to Step Type Displacement Rotation Step Step 2 Coupled temp displacement S t ep 2 Category Region Picked CSYS Global Edit Mechanical gt Displacement Rotation Method _ Specify Constraints Distribution Uniform 3 Pick the edge corresponding to the top Ul surface of the workpiece see Fig F6 UR3 radians Amplitude Ramp z 4 Set U2 0 25 Displace the workpiece o Cancel by 250 mm downwards 1 e to simulate the extrusion process v Temp BC 1 1 From the main menu bar select B C gt Create Name Temp BC 1 Type Temperature Step Step 1 Coupled temp displacement 2 Name it Temp BC 1 Assign to Step Region Picked Distribution Uniform Step 1 Category Magnitude 20 Amplitude Instantaneous x Other gt Temperature i OK Cancel
62. formation 3 From the main menu bar select Plot Contours gt On Undeformed Shape 4 From the main menu bar select Tools gt Path gt Create The Create Path dialogue box will open a Choose Edge list as the Type Fig 13 b Name the path Cantilever Path c Click Continue 5 The Edit Edge List Path dialogue box will open a Select Add After and OK b In the prompt area select By Feature Edge W Create Path O Node list Point list Edge list Circular Continue cancel Tw 33 Module 1 6 Using the mouse cursor select the first element edge a Click Flip and then Click Done in the prompt area 7 From the main menu bar select Tools gt XY Data Create The Create XY Data dialogue box will open Select Path Fig 14 and click Continue E Create XY Data Eg Source ODE field output Operate on XY data ASCII file Keyboard Path Continue Cancel 8 The XY Data from Path dialogue box will open Fig 15 a Select Cantilever Path from the Path options b Select Deformed from the Model Shape options c Select True Distance from the X Values option 9 Select the Field Output icon and the Field Output dialogue box will open Fig 16 a Select U as the primary variable and U2 as the component b Click OK and then click Plot in the XY Data from Path dialogue box c Click Save As and name the file Al_Deflection_Elastic_3D Click OK 10
63. he Field Output icon and the Field Output dialogue box will open f Select S as the primary variable and 811 from the Component options 39 Module 1 g Click Plot h Save the data To access the data from the main menu bar select Tools XY Data Edit 0 015 a tne 3D FEM Prediction 0 01 0 005 Y Position Across the Beami m 30 20 10 0 10 20 30 Stress S11 MPa Is there an easier way to obtain these data If you have time think about creating a node set at x 0 1 40 Module 1 Solution f e Compare these stress data with those from ordinary beam bending theory at x 0 7 for y 0 004 and y 0 0125 F L x 12F L x EI Ea i H 7 _W2F L x y y odA KE y2dA a a ie M KEI K MN ED 0 015 E a i a SS ify ify ri 0 da a T is if O A P ah eel ane 3D FEM Prediction O oo125 27 648 MPa C Analytical Prediction f 0 01 X 0 1 0 005 30 20 10 0 10 20 30 stress 511 MPa 41 Module 1 OPTIONAL TASKS 1 Assume now that the material behaves in an elastic perfectly plastic fashion and that the yield stress is 150 MPa Using the 3 dimensional finite element model compute the deflection of the cantilever beam when loaded at its end with a force of 600 N Hint you will have to define this plastic material behaviour in your material model 2 Using the 3 dimensional finite element mod
64. ig D9 ic i Incrementation Description Let workpiece cool down Type Automatic Fixed Maximum number of increments 200 lal F cir Tt l g n Response 0 Steady state Transient Initial Minimum Maimum Time period 10000 Increment size 100 0l 10000 Nigeom On E Use stabilization with dissipated energy fraction 0 0002 Max allowable temperature change per increment 100 E Include creep swelling viscoelastic behavior 83 Module 4 E MODULE gt INTERACTION a To create surfaces for interaction T Assembly Display Options General Datum Mesh Lights Attribute Instance l From the man menu bar select Note Suppressed instances or instances that do not belong to the current display group will not be visible even i P if their visibility is set on in this dialog View Assembly Display Options Use the Model Tree or Display Group Manager to resolve the conflict 2 Click the Instance tab toggle off the visibility of Mishin __ Home v Die 1 a Workpiece 1 Workpiece 1 see Fig E1 Click OK 3 From the main menu bar select Fig E1 Tools gt Surface gt Create Set All Off OK 4 Name the surface Surf die Contact pick the 5 edges designated in Fig E2 Tip To make multiple selections hold down the Ctrl button while clicking Pick this i 5 Return to Assembly Display Options to toggle on the visibility Fig E2 of Workpiece 1 then toggle off Di
65. in as the job name ensure that the Source Model chosen is 3D_Fin 3 Submit the job and monitor the progress Since this is a transient analysis longer computation time is expected may take 10 to 20 minutes depending on your system 4 When the job is completed from the Job Manager dialogue box click on Results I MODULE gt VISUALIZATION 1 From the main menu bar select A 330 00 Results gt History Output Plot the nodal S A 325 00 temperature of Set Node1 as a function of LLI Y 320 00 time Fig I1 It can be seen that it takes about m U 315 00 500 s to reach steady state conditions lt 310 00 2 To display the nodal temperature distribution 305 00 from the main menu bar select E 300 00 Results gt Field Output and select NT11 re 295 00 Fig I2 shows the temperature field at steady 290 00 Z 0 00 0 10 0 20 0 30 0 40 0 50 x10 State Time Note Using the control buttons in the context bar you can step though the frames to examine the temporal evolution of the thermal field 3 To display the heat flux distribution from the Field Output select HFL Fig I3 shows the temperature field HFL Magnitude Eni Ave Crit 75 at the steady state condition 399e 03 241e 0323 082e 03 924e 03 65e 03 607e 03 448e 03 290e 03 131e6 03 26e 02 141e 02 296E t02 971e 02 38 6e 02 8018 02 Module 2 J TASKS 1 Instead of using a transient model solve the abo
66. information calculate the absorbed energy energy lost by the projectile for impact velocities of 150 200 300 400 500 and 600 ms Module 3 Solution b e Return to the Property module Using the strain rate hardening and strain rate fracture data from Table and Table Il define strain rate hardening behaviour in your material model A MODULE gt PROPERTY 1 From the main menu bar select Material gt Edit gt Weldox 460E a Select Mechanical Plasticity Plastic b Under the Suboptions tab select Rate Dependent c Under Hardening select Johnson Cook and fill in the rate hardening data from Table 2 Select Ductile Damage from the Material Behaviours box Fill in the rate dependent fracture strain data as shown in Table Il B MODULE JOB 1 Determine the ballistic limit of the plate with these new material property characteristics by submitting the necessary jobs You may need to alter the step time for low impact velocities Submit 5 further jobs at impact speeds between the ballistic limit and 600 m s C MODULE VISUALISATION 1 View the Mises Stress contours by selecting Results gt Field Output from the main menu bar Calculate the absorbed energy by extracting the projectile velocity history Module 3 OPTIONAL QUESTIONS 1 Determine the ballistic limit of the plates when struck at an angle of 45 2 The effects of friction have not been considered in these analyses Using the FE model a
67. is right click within the table and choose Read from File F4 Use strain rate dependent data v Use temperature dependent data Number of field variables 05 Data Yield Stress Table 1 Temperature dependent flow stress of Aluminium Yield stress Plastic strain Temp 6 00E 07 0 20 9 00E 07 0 125 20 1 13E 08 0 25 20 1 24E 08 0 375 20 1 33E 08 0 5 20 1 65E 08 1 20 1 66E 08 2 20 6 00E 07 0 50 8 00E 07 0 125 50 9 70E 07 0 25 50 1 10E 08 0 375 50 1 20E 08 0 5 50 1 50E 08 1 50 1 51E 08 2 50 5 00E 07 0 100 6 50E 07 0 125 100 8 15E 07 0 25 100 9 10E 07 0 375 100 1 00E 08 0 5 100 1 25E 08 1 100 1 26E 08 2 100 4 50E 07 0 150 6 30E 07 0 125 150 7 50E 07 0 25 150 8 90E 07 0 5 150 1 10E 08 150 1 11E 08 150 6E 007 9E 007 1 13E 008 1 24E 008 1 33E 008 1 65E 008 1 66E 008 6E 007 or nna OK Cancel gt oN OM ew Ne 19 Module 4 b To enter material properties of the die l From the main menu bar select Material gt Create 2 Name the material Die Material 4 Create the following material properties Note Since the die will be modelled as a rigid body and heat flow into the die is not modelled the properties entered here will be inconsequential However non zero values must be entered so that the ABAQUS CAE solver can proceed 1 General gt Density 2700 kg m ii Thermal gt Conductivity 200 W m K Gii Thermal gt Specific Heat 880 J kg K iv Mechanical gt
68. isp Explicit creep swelling viscoelastic behavior Geostatic Heat transfer Mass diffusion r 4 In Edit Step dialog box click on the Incrementation tab Fig D4 and reduce the Initial Increment size to 0 1 Toggle on Max allowable temperature change per increment and enter 100 5 Accept the default settings under the Other tab i Edit Step Name Step 1 Type Coupled temp displacernent Fig D4 a Edit Step Name Step 1 lacement Fig D3 Type Automatic Fixed Description Stabilise workpiece inside die Response Steady state Transient Maximum number of increments 1000 Time period 1 Initial Minimum Maximum Increment size 0 1 1E 005 1 Nigeom On E Use stabilization with eared aay ean 9 0002 Max allowable temperature change per increment 100 Include creep swelling viscoelastic behavior L Creep swelling viscoelastic strain error tolerance Creep swelling viscoelastic integration Explicit Implicit Explicit b To create Step 2 Extrusion Create Step 2 As of Step 1 the Procedure type is Coupled temp displacement Figs D5 and D6 show the parameters to be used a Edit Step E Edit Step Name Step 2 Type Coupled temp displacement Fig DS ic i Incrementation Description Extrusion Type Automatic Fixed Response Stea dy state D Transient Maximum number of increments 800 Initial Minimum Maximum Increment
69. it for analysis You can also view and edit the analysis keywords for a model by selecting Model Edit Keywords model name from the main menu bar Visualisation The Visualisation module provides graphical display of finite element models and results It obtains model and result information from the output database you can control what 12 information is placed in the output database by modifying output requests in the Step module You can view your model and results by producing any of the following plots ee Undeformed shape An undeformed shape plot displays the initial shape or the base state of your model Sy Deformed shape A deformed shape plot displays the shape of your model according to the values of a nodal variable such as displacement a Contours A contour plot displays the values of an analysis variable such as stress or strain at a specified step and frame of your analysis The Visualisation module represents the values as customised colored lines colored bands or colored faces on your model Eem Symbols A symbol plot displays the magnitude and direction of a particular vector or tensor variable at a specified step and frame of your analysis The Visualisation module represents the values as symbols for example arrows at locations on your model Are Material orientations A material orientation plot displays the material directions of elements in your model at a specified step and frame of
70. l c To create a rigid body constraint for the die 1 From the main menu bar select Constraint E Edit Constraint gt Create Name Die RigidBody 2 Name the constraint Die RigidBody Under bee Pee cee ae Type select Rigid body Body elements Picked Pin nodes 3 The Edit Constraint dialogue box appears Fig E6 ee Under Region type choose Body elements and Reference Point Point Picked E Adjust point to center of mass at start of analysis Just p then pick the die region Constrain selected regions to be isothermal i coupled thermal stress analysis only p 4 For Reference Point pick the yellow point denoted as RP see Fig A3 i e the reference point of the die 5 Toggle on Constraint selected regions to be isothermal 85 Module 4 d To create the interactions We will create 3 interactions the end result is shown in Fig E7 Note that not all interactions are active at all steps A Interaction Manager Name Initial Step 1 Step 2 Step 3 Step 4 w CONVECT Created w INTER H Created Propagated Propagated Inactive Inactive INTER V Created Propagated Propagated Inactive Inactive REECE SIE Activate Deactivate Step procedure Coupled temp displacement Interaction type Surface film condition Interaction status Created in this step E Create Interaction e Thermal film interaction Name CONVECT Step Step 4 1 From the main menu bar
71. l displacement at nodes Fig A2 There is a tensile state of axial stress at the top of the beam and a compressive axial stress Invariant Component SS state at the bottom The peak tensile and Max Principal Mid Principal compressive stresses are 41 MPa Fig A1 Pressure To liset oT oeoreretodot Ha lt bo Be oa 38 Module 1 3 To plot the distribution of stress through the beam at x 0 7 complete the following set of tasks 4 From the main menu bar select Tools Path gt Create The Create Path dialogue box will open as in Fig A3 W Create Path a Name the path Stress Path ame Stress Path b Choose Node List for the Type c Click Continue i Edge list d From the Edit Path List dialogue box that Circular opens select Add Before Continue 5 The length of the beam is 1 m Since the beam has been meshed with 200 elements along the edge the position x 0 1 is equal to 20 elements along the beam Using the cursor select the nodes across the beam at x 0 1 as shown Click OK in the Edit Path List dialogue box 2 H 6 From the main menu bar select Tools gt XY Data Create The Create XY Data dialogue box will open a Select Path and click Continue b Choose Stress Path as the path from the XY Data from Path dialogue box c Choose Deformed for the Model Shape d Under X Values Toggle on Y Distance e Click t
72. lect both the Brick and Concrete regions E ea aa Free Minimize the mesh transition Tip you can do this by dragging a box across them E turei D Advancing front Be Click Done on the prompt area 3 The Mesh Controls dialog box appears follow the settings depicted in Fig F1 Ensure that Medial axis algorithm is chosen c To assign element type 1 From the main menu bar select a Element Type Mesh Element Type Element Library Family D Explicit Gasket 1 i Generalized Plane Strai 2 Select both regions Click Done i Eee eneralized Plane Strain Heat Transfer Linear Quadratic Piezoelectric 3 The Element Type dialog box Quad Tri Element Controls Convection Diffusion appears Fig F2 under the Family Dispersion control list ensure that Heat transfer is DC2D4 A 4 node linear heat transfer quadrilateral selected The element type to be assigned is DC2D4 d To mesh the part instance 1 From the main menu bar select Mesh gt Instance 2 Select both regions Click Done The generated mesh should resemble Fig F3 Fig F3 Module 2 G MODULE gt JOB a To create a new job 1 From the main menu bar select Job Create 2 The Create Job dialog box appears enter Job 2D Thermal Click Continue 3 The Edit Job dialog box appears accept the default settings and click OK b To submit the job 1 From the main menu bar select Jo
73. ment for any ABAQUS element that is topologically equivalent to the element shape assigned to the region As a result you can choose to mesh a shell region with only all triangular elements and ABAQUS CAE ignores the quadrilateral element assignment To change the element assignment to an ABAQUS element that is topologically equivalent to the element shape assigned to the region select Mesh Element Type from the main menu bar Similarly you can select Mesh Controls to select the element shape for meshing However since no element type checking is done until you submit the analysis it is possible to choose an element that is inappropriate for the analysis you will be conducting For example Abaqus CAE does not prevent you from specifying heat transfer elements such as DC2D4 even though you may be conducting a stress analysis Job Once you have finished all of the tasks involved in defining a model such as defining the geometry of the model assigning section properties and defining contact you can use the Job module to analyze your model The Job module allows you to create a job to submit it to Abaqus Standard or Abaqus Explicit for analysis and to monitor its progress If desired you can create multiple models and jobs and run and monitor the jobs simultaneously In addition you have the option of creating only the analysis input file for your model This option allows you to view and edit the input file before submitting
74. nd assuming a friction co efficient between the projectile and the plate of 0 18 determine whether or not there is a contribution to absorbed energy from friction How much more significant is friction when the angle of incidence is 45 compared to when the plate is struck at normal incidence for an impact velocity of 300 m s Hint return to your contact interaction property and search under tangential behaviour 3 The strain and strain rate dependent behaviour has been described using the Johnson Cook constitutive relation Is there an alternative way of defining this data in the material editor 4 In the strain rate dependent simulations you defined rate dependent fracture strains for strain rates as high as 10000 s Is this strain rate dependent fracture data sufficient to cover the range of strain rates that are generated at the highest impact velocities Hint you will need to edit the field output requests to include strain rates as output data 74 Module 4 Fully Coupled Thermo Mechanical Analysis Type of solver ABAQUS CAE Standard Adapted from ABAQUS Example Problems Manual Extrusion of a Cylindrical Aluminium Bar with Frictional Heat Generation Problem Description The figure below shows the cross sectional view of an aluminium cylindrical bar placed within an extrusion die The bar has an initial radius of 100 mm and a length of 300 mm and its radius is to be reduced by 33 through an extrusion process The die
75. ndard Elastic foundation Actuator sensor 3 For the master surface select Surf die Contact Le choose the stiffer of the pair 4 Choose the slave type as Surface then select Continue Surf workpiece Horizontal 5 The Edit Interaction dialogue box Fig E12 appears Set Degree of smoothing for master Edit interaction Mame INTER H surface as 0 48 Accept the rest of the Type Surface to iae cones eee Fig E12 default settings Note that the Contact a Master surface Surf die Contact W interaction property is I1NEPY op 1 which Slave surface Surf workpiece Horizontal M Sliding formulation Finite sliding Small sliding Was created earlier Mm a Discretization method Node to surface 6 Now using similar procedures create an Degree of smoothing for master surface 0 48 interaction for NTeR v Assign Use supplementary contact points Selectively Never Always Surf die Contact as the master surface Surface Smoothing Clearance No adjustment and S u E f WO r kp 1 e C e Ve EC 1 C a l as the i 3 i Adjust only to remove overclosure Specify tolerance for adjustment zone 0 slave O Adjust slave nodes in set 7 We also need to make INTER H and INTER V inactive during Step 3 Remove Contact interaction property IntProp 1 contact pairs and Step 4 Let workpiece Options Contact controls Default cool down From the main menu bar select
76. nits Base dimensions Length in meters m Force in Newtons N Time in seconds s The following dimensions need to be used Pressure N m2 Pa Stress N m2 Pa Case 2 SI units small parts Base dimensions Length in millimeters mm Force in Newton N Time is seconds s The following dimensions need to be used Pressure N mm2 1e6 Pa MPa Stress N mm 1e6 Pa MPa Velocity m s Acceleration m s2 Mass kg Volume m Density kg m3 Energy Nm J Velocity mm s 1e 3 m s Acceleration mm s2 le 3 m s2 Mass Mg 1e3 kg Volume mm 1e 9 m2 Density Mg mm3 1e12 kg m Energy 1e 3 J mJ Usage example ifthe density 1000 kg m then in the FE program specify the Case 3 SI units small loads Base dimensions Length in micrometers um Force in micro Newtons uN Time in seconds s density as 1000e 12 The following dimensions need to be used Pressure 1e6 Pa MPa Stress 1e6 Pa MPa Velocity 1e 6 m s um s Acceleration 1e 6 m s2 um s2 Mass kg Volume 1e 18 m3 Density 1e18 kg m3 Energy 1e 12 Nm pJ Web PolymerFEM com Email jorgen polymerFEM com Jorgen S Bergstrom
77. nt 6 Create a set at the Reference Point and call it Projectile Set Reference Point o Module 3 B MODULE PROPERTY In this module property you will define the plate material properties The strain hardening behaviour will be described using the Johnson and Cook plasticity relation Fracture will be modelled by defining a critical plastic strain 1 From the toolbox select the Create Material tool The Edit Material dialogue box will open a Name the material Weldox 460E b Define the density and elastic constants Table Ill c Select Mechanical gt Plasticity Plastic as shown in Fig B1 d Under Hardening select Johnson Cook Fig B2 Fill in the data according to Table I e To define the critical plastic strain at fracture select Mechanical gt Damage for Ductile Metals Ductile Damage Fig B3 The quasi static fracture strain is 0 33 The stress triaxiality is 0 33 and the reference strain rate is 0 01 f In the Suboptions drop down menu select Damage Evolution Fig B4 Choose a Displacement at Failure value of 0 0001 Fig B5 Click OK Click OK again E Fii Material a Edit Matorial J E faii Material Hiran Wokka 4E hana Wekjox 4 G Mand wabia 40 escription Darii Diir ipti stens Borisas Daat if Meria Baharini Mitran Berane Gereral pecha Thermal gahar ZA Ulssbety Ciistie Bailie Dha Piti Type ip Damage for Cayoile Meta F Cip Plathitity Cl Lisa ter EUe ter Dems
78. ntended to provide comprehensive coverage of linear and nonlinear isotropic and anisotropic material behaviours The use of numerical integration in the elements including numerical integration across the cross sections of shells and beams provides the flexibility to analyze the most complex composite structures Some of the mechanical behaviors offered are mutually exclusive such behaviors cannot appear together in a single material definition Some behaviors require the presence of other behaviors for example plasticity requires linear elasticity A material definition can include behaviors that are not meaningful for the elements or analysis in which the material is being used Such behaviors will be ignored For example a material definition can include heat transfer properties conductivity specific heat as well as stress strain properties elastic moduli yield stress etc When this material definition is used with uncoupled stress displacement elements the heat transfer properties are ignored by Abaqus when it is used with heat transfer elements the mechanical strength properties are ignored This capability allows you to develop complete material definitions and use them in any analysis For a comprehensive introduction on how to define material property data students are advised to consult section 17 1 2 of the ABAQUS user manual Material Data Definition Units Abaqus has no units built into it except for rotation and
79. nu bar select Part gt Create Modeling Space i 3D O 2DPlanar Axisymmetric 2 The Create Part Dialogue box appears Name the part Steel Plate and fill in the options as shown in Fig A1 Click Continue to create the k aa part O Discrete rigid None available Analytical rigid 3 From the main menu bar select Add gt Circle onan a Select the co ordinates 0 0 for the centre of the circle in the Base Feature Fig A1 prompt area Sheps e O soli b Select the co ordinates 0 04 0 for the perimeter point shel Extrusion Revolution Sweep O wire Point c Click and then Done in the prompt area 4 You must now create two partitions From the main menu bar Approximate size 0 1 Continue Cancel select Tools Partition The Create Partition dialogue box will open Fig A2 W Create Partition Type O Edge Face Cell b Using the mouse cursor select the edge of the part Method Sketch a Select Face as the Type and Sketch as the Method Use shortest path between 2 points c Using the Create Circle tool create two circles one with a Use datum plane Use curved pi i i i Extend anoth diameter of 70 mm and the other with a diameter of 10 mm Fig A2 d Click and then Done in the prompt area 5 Now create an Analytical Rigid spherical projectile with an 8 mm diameter Fig A3 Once done create a Reference Point at the centre Tools gt Reference Poi
80. ocity Connector displacement 4 Set U1 U2 UR3 0 To ensure that the die remains Connector velocity static throughout the simulation see Fig F3 a Edit Boundary Condition Continue Name Disp BC 1 Type Displacement Rotation Step Step 1 Coupled temp displacement Region Picked CSS Global Edit Distribution Uniform Ul 0 U 0 URS Q Amplitude Rarnp 88 Module 4 1 Disp BC 2 1 From the main menu bar select BC gt Create Name Disp BC 2 i Type Displacement Rotation 2 Name it D La P 7 B C 7 2 Assign to Step Step Step 1 Coupled temp displacement Region Picked Step 1 Category CSYS Global Edit Mechanical gt Displacement Rotation Distribution Uniform v U1 0 U2 3 Pick the edge corresponding to the axis iad Amplitude Ramp z of the workpiece see Fig F4 uA Cancel 4 Set Ul 0 To ensure that the workpiece remains axisymmetric throughout the simulation Gul Disp BC 3 1 From the main menu bar select BC gt Create 2 Name it Disp BC 3 Assign to Step Pick this edge Mechanical Displacement Rotation 4 Name Disp BC 3 Type Displacement Rotation Step 1 Category Step Step 1 Coupled temp displacement Region Picked 3 Pick the edge corresponding to the top surface of the workpiece see Fig F5 CSYS Global Edits Distribution Uni
81. odel Cantilever_1D A MODULE PART Under the Part module we will construct the beam 1 D 1 From the main menu bar select Part gt Create 2 The Create Part Dialogue box appears Name the part Cantilever Beam and fill in the options as shown in Fig A1 Click Continue to create the part 3 From the main menu bar select Add Line gt Connected Line a Select the co ordinates 0 0 for the first vertex enter as shown in Fig Az2 b Select the co ordinates 7 0 for the second vertex enter c Click X in the prompt area d Click Done in the prompt area Pick a starting point for the line or enter X Y lo 0 Approximate size Z Continue Cancel MS Create Part Mame Cantilever Beam Modeling Space 3D 2D Planar Axisymmetric Type Options Deformable Discrete rigid None available Analytical rigid Base Feature Shell Wire Paint Fig A1 The part Cantilever Beam will now appear in the Viewer window as a 1 dimensional beam The following tasks must be completed e The beam section geometry must be defined e The beam material properties must be defined e The boundary conditions constraints and loads must be defined e A mesh must be assigned 16 Module 1 B MODULE gt PROPERTY In this module property you will define the beam geometry width and height you will define the
82. of analysis types Click Continue and OK E MODULE gt INTERACTION There are no interactions in this analysis F MODULE gt LOAD In the load module you define the boundary conditions constraints and loads You will constrain one end of the cantilever beam to be fixed zero displacements and you will define an 80 N load at the free end of the beam 1 From the main menu bar select Load gt Create The Create Load Dialogue box will open Fig F1 E Create Load a Name the load Concentrated Load Step Load Step b Choose Load Step as the Step option Procedure Static General f Category Types for Selected Step c Choose Mechanical for the Category Mechanical Moment d Choose Concentrated Force for the Type aceon Shell edge load Surface traction e Click Continue Electrical Pipe pressure Body force i ine load f Using the mouse cursor select the second Fig F1 mee vertex node Bolt load Continue Cancel g Click Done in the prompt area 2 The Edit Load dialogue box will open as shown in Fig F2 You now need to specify a transverse load of 80 N a Input CF1 0 load in the x direction EE Edit Load Name Concentrated Load b Input CF2 80 load in the y direction Type Concentrated Force Step Load Step Skatic General c Toggle off Follow Nodal Rotation Region Picked This ensures that the load is continuously applied in the y cS
83. of freedom are expressed in radians and all other angle measures are expressed in degrees for example phase angles Assembly When you create a part it exists in its own coordinate system independent of other parts in the model In contrast you use the Assembly module to create instances of your parts and to position the instances relative to each other in a global coordinate system thus creating the assembly You position part instances by sequentially applying position constraints that align selected faces edges or vertices or by applying simple translations and rotations Move the parts about using the translate features Figure 4 Assembly of part instances An instance maintains its association with the original part If the geometry of a part changes Abaqus CAE automatically updates all instances of the part to reflect these changes You cannot edit the geometry of a part instance directly A model can contain many parts and a part can be instanced many times in the assembly however a model contains only one assembly Loads boundary conditions predefined fields and meshes are all applied to the assembly Even if your model consists of only a single part you must still create an assembly that consists of just a single instance of that part A part instance can be thought of as a representation of the original part You can create either independent or dependent part instances An independent instance is effectively a cop
84. pe as Surface E Edit Constraint Name Interface click on the gt faces button at the lower right hand Type Tie corner of the prompt area Select Brick inside Master surface Brick inside i Slave surface Concrete outside fj and click Continue Click the Surface button in the Constraint enforcement method Analysis defaun fil prompt area and select Concrete outside as the BE Eta ee Position Tolerance slave surface Click Continue Use computed default Specify distance 4 The Edit Constraint dialog box appears Fig E1 Note Modes on the slave surface that are considered to be outside the position accept the default settings and click OK toleran E Adjust slave surface initial position b To assign convective heat transfer conditions Tie rotational DOFs if applicable 1 From the main menu bar select Interaction gt Create 2 The Create Interaction dialog box appears Fig E2 name it Int InnerWalls Under Step choose Heating For Types for Selected Step choose Surface film condition click Continue In the Region Selection dialog box select the surface defined earlier as Concrete inside and click Continue Note if the Region Selection dialog box does not appear click on the gt faces button at the bottom right hand corner of the prompt area 3 The Edit Interaction dialog box appears Fig E3 enter 0 208 W m K as the Film coefficient and 1273 K as the Sink temperature 4
85. redictions Problem Description You have been asked by the Ministry of Defence to determine the ballistic limit minimum impact velocity required to fully perforate a target of 0 4 mm thick steel plates impacted by spherical projectiles that are 8 mm in diameter The projectiles have a mass of 0 002 kg The steel mechanical properties have been measured for you The plastic mechanical behaviour is well described by the Johnson and Cook phenomenological plasticity model 63 Module 3 Johnson Cook Theory The Johnson amp Cook phenomenological plasticity relation defines the flow stress as a function of equivalent plastic strain strain rate and temperature The model is frequently used in impact analyses because of its simplicity One other major benefit of this model is that the various phenomena such as strain hardening strain rate hardening and temperature softening can be uncoupled When only strain hardening and temperature softening are coupled the effective stress is given by 1 T A BE D d 6 When strain rate hardening is deemed to be significant then the dynamic flow stress is expressed by the following relation n Ey Am 2 T A B E 1 Cln 0 8 Eo where o is the dynamic flow stress is the equivalent plastic strain E is the equivalent plastic strain rate fy is a reference strain rate A B n m and C are material parameters and 6 is the non dimensional temperature The constant
86. size 0 1 0 0001 10 Time period 10 Nigeom On A i Max allowable temperature change per increment 100 E Use stabilization with dissipated energy fraction 0 0002 E Creep swelling viscoelastic strain error tolerance Include cree elling viscoelastic behavi EAEE aati Creep swelling viscoelastic integration Explicit Implicit _ Explicit Module 4 c To create Step 3 Remove contact pairs Create St ep 3 and fill out the parameters as in Figs D7 and D8 E Edit Step Name Step 3 Type Coupled temp displacement Fig D8 a Edit Step Name Step 3 Type Coupled temp displacement Fig D7 ic i Incrementation Type Automatic Fixed Description Remove contact pairs p P Maximum number of increments 200 Response C Steady state Transient Initial nmm Maima Time period 0 1 Increment size 0 1 1E 006 0 1 Nigeom On Max allowable temperature change per increment 100 E Creep swelling viscoelastic strain error tolerance C Use stabilization with dissipated energy fraction 0 0002 Include creep swelling viscoelastic behavior Creep swelling viscoelastic integration Explicit Implicit Explicit d To create Step 4 Let workpiece cool down Create St ep 4 and fill out the parameters as in Figs D9 and D10 a Edit Step Name Step 4 Type Coupled temp displacement Fig D 1 0 E7 Edit Step Mame Step 4 Type Coupled temp displacement F
87. t Obtain the deflected profile Tools XY Data Create The Create XY Data dialogue box will open Select Path Compare the FEM predictions with those from beam bending theory 0 01 0 01 0 02 0 03 0 04 Analytical Prediction 3 Dimensional FEM Model 5000 C3D20R Elements 0 05 Q 0 2 0 4 0 6 0 8 1 x Position m The error now falls to 0 17 37 Module 1 Solution e e Return to the Mesh module and change the element type Mesh gt Element Type Select Quadratic from the Geometric Order Choose C3D20R elements A MODULE VISUALISATION 1 From the main menu bar select Results gt Field Output The Field Output dialogue box will open Fig A1 E Field Output Step Frame a Select S as the primary variable Step 1 Load Step Frame 1 Paleary Variable Deformed Variable b Select S11 as the stress component Output Variable axi al st r e S S _ List only variables with results Name Description indicates complex AC YIELD Active yield flag at integration points 1 Point loads at nodes c Click OK Logarithmic strain components at integration points Plastic strain components at integration points i g PEEQ Equivalent plastic strain at integration points 2 The stress distribution will appear as shown In PEMAG Magnitude of plastic strain at integration points RF Reaction force at nodes s Swess components atintegraton ponts U Spatia
88. t Add Before from the Viewport ME Edit Edge List Path Selection options Name Cantilever Path Type Edge List Path Definition Part Instance 1 CANTILEVER BEAM 1 b In the prompt area choose Feature Edge Fig I6 c Using the mouse cursor select the first element of the beam in the Viewer Venport selecione iin by feature edge ne by feature edge by shortest distance d Click Done in the prompt area and OK in the Edit Edge List Path dialogue box The nodes that form the path will be identified as shown in Fig I7 Fig 17 2 E Cancel Select edges to be inserted into the path nd 21 Module 1 6 From the main menu bar select Tools gt XY Data Create The Create XY Data dialogue box will open Select Path from the list of options and click Continue The XY Data from Path dialogue box will open Fig 18 a Select Cantilever Path from the Path options b Select Deformed from the Model Plot options c Select True Distance as shown d Clicking the Field Output icon will bring up the Field Output dialogue box Fig 19 e Select U as the primary variable and U2 as the Component Click OK f To view the path plot click Plot g Save the data by clicking Save As and name the data Al_Deflection_Elastic_1D EE XY Data from Path x E Field Output Data Extraction Path Modelshape Deformed Undeformed Point Locations Step Frame Step 1 Load Step
89. t NT11 and click OK to produce the nodal temperature distribution plot Fig H1 Sl e 02 7 e Note The temperature is in Kelvin 980e 02 644e 02 tte m r e Click on Contour Options on the 63 5e 02 B 962e 02 prompt area and you ll be presented with various ways of customising the output To display the heat flux distribution within the walls from the main menu bar select Results gt Field Output HFL Magnitude Crit 75 3 1 153e 00 The Field Output dialog box See 417e 00 appears under Primary Variable 6816400 3136 00 945e 00 select HFL and click OK The heat 5776400 TEA 2 e fluxes shown here are in Wm 474e 00 106e 00 i gaiet e Fig H2 consistent with the SI unit 0026100 lt e we employed while setting up the oo model To generate a resultant vector plot of the heat fluxes Fig H3 from the HFL Resultant main menu bar select Plot gt Symbols Click on Symbol Options on the Fig H3 prompt area to customise the vector alll SEET EL ETARE plot lllh a ANAE I EEEE i RRENA TEER BN MreTS p lf mye a se Mlle ed er Ny ee Pee 1 2 44 Cas FS ag 3i am Mi ern amp k b k a I J b i e 51 Module 2 TASKS 1 Due to symmetry it is possible to model a quarter or just one eighth of the system by applying suitable boundary conditions Demonstrate how this could be done in A
90. t of Cancel the loading direction however by default ABAQUS requires a beam orientation to be defined for all beam sections 5 From the main menu bar select Assign Assign Beam Section Orientation Use the mouse cursor to select the part in the Viewer and click Done in the prompt area The default orientation can be selected by pressing Enter clicking OK and then clicking Done C MODULE gt ASSEMBLY In the assembly module multiple parts can be assembled into an MM Create Instance assembly of parts This is done by creating instances of each part Parts In this case we have only one part Cantilever Beam ABAQUS still requires however that an instance of this part is created FYI multiple instances of a single part can be created if required Instance Type Dependent mesh on part 1 From the main menu bar select Instance gt Create The Create Note To change a Dependent instance s Instance dialogue box will open Fig C1 mesh you must edit its part s mesh C Auto offset from other instances a Under Instance Type select Independent In the step module you will define the type of analysis that is to be undertaken static in this case 1 From the main menu bar select Step Create The Create Step dialogue box will appear Fig D1 Name the step Load Step Module 1 2 Select General from the Procedure Type options 3 Select Static General from the list
91. tart and end points for the translation vector position the smaller concrete wall within the larger brick wall so that the final assembly resembles Fig C3 D MODULE gt STEP 1 From the main menu bar select Step gt Create E Create Step Name Heating 2 The Create Step dialog box appears Fig D1 name it Insert new step after Heating and select Heat transfer under Procedure type intial sid Click Continue 3 The Edit Step dialog box appears Under the Basic tab toggle Fig D1 on Steady state click OK Procedure type General u s PPE Prk LEE LD elites 4 From the main menu bar select Output History Output Dynamic Explicit i Dynamic Temp disp Explicit Requests Create accept the default name H Output 1 Geostatic Heat transfer Mass diffusion the Edit History Output dialogue box appears expand the Thermal button and toggle on FTEMP Click OK Static General Ctatie Bike Continue Cancel E MODULE gt INTERACTION a To tie the nodes at the interfaces yr 1 From the main menu bar select Constraint Create 2 The Create Constraint dialog box appears name it Interface and under Type pick Tie Click Continue Note since we assume there is no thermal resistance across the brick concrete wall interface the Tie constraint will equate temperatures at the matching nodes 47 Module 2 3 Inthe prompt area choose the master ty
92. tion Transient and set the Time period Nigeom Off as 5 0 0 0 seconds Response Steady state Transient Fig D1 Time period 3000 Click on the Incrementation tab Fig D2 increase the Maximum number of increments to 200 Change the Initial Increment size to 0 1 and i E Edit Step Maximum Increment size to 100 Name Transient heating Type Heat transfer Fig D2 Type Automatic Fixed Toggle on End step when temperature change is less than and enter 0 0001 SO that iteration Maximum number of increments 200 eg Initial Minimum Maximum will stop once thermal equilibrium Increment size 0 1 0 05 100 is reached End step when temperature change ts less than 0 0001 Max allowable temperature change per increment 5 Set the Max allowable Max allowable emissivity change per increment 0 1 temperature change per increment to 5 Kelvin Accept the default settings under the Other tab b To edit the field output l 2 From the main menu bar select Output Field Output Requests gt Edit gt F Output 1 Under Output Variables toggle on Thermal and select NT and HEFL 56 Module 2 c To edit the history output 1 First we create a node set to record the temperature history From the main menu bar Set Node1 select Tools gt Set gt Create The Create Set dialog box appears name it Set Node1 and pick the node depicted in Fig D3 2 From the main menu b
93. ve problem using a steady state model 2 Compute the temperature gradients across different sections of the heat sink Investigate how sensitive the solutions are toward the choice of mesh size and or element type 3 How could one modify the current heat sink design to reduce the time for it to reach steady state conditions Demonstrate through a comparative FE analysis 4 In practice it s most likely that the heat flux at the base of the heat sink will vary as a function of time say by increasing linearly from 0 to 1000 W m over 200 sec How can you model such a changing boundary condition in ABAQUS 62 Module 3 Plate Perforation Analysis Type of Solver ABAQUS CAE Exoplicit Dynamic Analysis Plate Perforation from Projectile Impact Introduction Perforation of metallic plates during projectile impact is a complex process commonly involving elastic and plastic deformation strain and strain rate hardening effects thermal softening crack formation adiabatic shearing plugging petalling and even shattering These effects depend on the properties and geometries of projectile and target and on the relative velocity of the colliding bodies In this practical class you will model the perforation of a deformable metallic plate when struck by a rigid spherical projectile over a range of impact velocities You will run analyses assuming both rate dependent and rate independent material behaviour and compare your p
94. y of the part A dependent instance is only a pointer to the part partition or virtual topology and as a result you cannot mesh a dependent instance However you can mesh the original part from which the instance was derived in which case Abaqus CAE applies the Same mesh to each dependent instance of the part Note that dependent part instances are less expensive computationally although not much Step You can use the Step module to perform the following tasks Create analysis steps Specify output requests Specify adaptive meshing Specify analysis controls Create analysis steps e Within a model you define a sequence of one or more analysis steps The step sequence provides a convenient way to capture changes in the loading and boundary conditions of the model changes in the way parts of the model interact with each other the removal or addition of parts and any other changes that may occur in the model during the course of the analysis In addition steps allow you to change the analysis procedure the data output and various controls You can also use steps to define linear perturbation analyses about nonlinear base states You can use the replace function to change the analysis procedure of an existing step Specify output requests e Abaqus writes output from the analysis to the output database you specify the output by creating output requests that are propagated to subsequent analysis steps An output request d
95. your analysis The Visualisation module represents the material directions as material orientation triads at the element integration points X Y data 13 Module 1 Cantilever Beam Bending Analysis Type of Solver ABAQUS CAE Standard TLP Bending and Torsion of Beams htto www doitooms ac uk tlolib beam_bending index php Continuum Mechanics Beam Bending Problem Description Consider the cantilever beam shown below The beam is made from aluminium which has a Young s modulus of E 70 GPa a shear modulus of G 25 GPa and a Poisson s ratio of v 0 33 The beam is 1 min length L 1 and has a square section with a b 0 025 m When a transverse load is applied at some distance x along the beam length a bending moment M is generated where d y M EI 2 F L x i X The deflection of the beam is given by _ Fx GL x 6EI I is the second moment of area For a square cross section X is the distance from the clamped end 14 Module 1 a Using a 1 dimensional finite element model compute the deflection of a cantilever beam loaded at its end with a force of 80 N Compare the FEM predicted deflections with those predicted by ordinary beam bending theory Assume that the beam is made from aluminium is homogenous and isotropic and that it behaves in a linear elastic fashion b Using a 3 dimensional finite element model compute the deflection of a cantilever beam lo

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