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LSMS (1.0) USER MANUAL

1. att 7 e M Q H 2 i 2 LL Copy Graph OK Cancel Figure 6 The User defined source dialogue box The variation of a user defined source is controlled by using the View Edit Source button to launch the User defined source dialogue box shown in Figure 6 This allows you to control the time variation of the source during the simulation You must always define the flow rate and temperature of the incoming liquid and if the liquid is multicomponent you must define the composition of the incoming liquid as well by setting the volume fractions of the components You define the variation of the source variables by entering a set of time and value pairs for each one During the simulation these sets of time and value pairs will be used to find values at the current time If the current time is between two specified times linear interpolation will be used to find the current value Once the last specified time has been passed the value is assumed to remain constant at the last value you entered For example if only one time and temperature pair is given the temperature of the inflowing liquid stays constant throughout the simulation Consequently to define a source of finite duration you must specify a final flow rate of zero explicitly 4 feo A Section 4 The LSMS input data Each variable is edited independently by choosing the current variable from the list box at the top left of the dialogue
2. ERRORS TXT Contains the warning messages which are logged by the simulation DATA PAGELAY TXT Contains the page layouts for printing graphs DATA LIQUID Contain the details of the liquids in the pre defined database including newly defined liquids 50 od m Section 8 The LSMS files 8 3 Help files FILE DESCRIPTION GRAPHPPD HLIP Help file for the graphics module GRAPHPPR HLP_ Second help file for the graphics module 8 4 Resources These files provide various resources for the LSMS interface THREEDVBX O HTRUEGRIDVBX zx Wi Section 9 Files produced for each problem 9 Files produced for each problem 9 1 A list of the files produced for each problem considered Extension LPL Main input file Contains all input data except user defined source details User defined source data Format given in Section 9 3 SR C LD1 and LD2 Binary output files Contain the detailed record of the simulation results LOG Log file Record of the simulation progress A ST Statistics file Contains statistics on the overall simulation SPL Spill file Created when the problem is selected as a primary source for a secondary spill Contains details of the overtopped fluid Format given in Section 9 2 ERR Error file Created when the simulation terminates for communication with the interface Indicates whether the simulation completed successfully G01 G02 etc Graph files Contain detail
3. be loaded with the data generated from the LSMS results and displayed so that the input data for the GASTAR run can be completed If you have chosen to use the pool uptake model the interface will be open at the appropriate dialogue box 6 2 2 Creating HAGAR files LSMS has the facility to create a set of input files for HAGAR from the results of a simulation To produce HAGAR files choose Make HAGAR Files from the Dispersion menu The dialogue box in Figure 29 will be displayed Specify the partitioning of the LSMS run into segments as explained in Section 6 2 1 When you select the OK button on the dispersion time domain dialogue box another dialogue box appears asking you to complete the rest of the input data for a HAGAR file Figure 30 Some of the entries will have been filled in with data derived from the LSMS data The rest should be filled in by the user Users are referred to the HAGAR documentation for definitions of the data items used by HAGAR 42 Section 6 Further features HAGAR parameters From LSMS run C PROJECTSSLSMSATESTSSINSTKWI2 LP 000 Conan 103 6043 Figure 30 HAGAR parameters dialogue box 6 2 3 Creating files for a generic dispersion model LSMS can also create text files containing details of the vaporisation during the simulation These files are designed to be easily converted to alternative file formats To produce a file of this kind choose Make Generic File from the Disper
4. 0 Max 10000 The main LSMS window has a help bar at the bottom This gives you information about the part of the interface you are currently using in the form of a short description of the item If you are entering a numeric value the maximum and minimum permissible values will be displayed and you will be prevented from entering values outside this range In Figure 1 the help bar is giving details for the source radius which can be between 0 m and 100 m 3 1 3 Enabled and disabled items Items in the interface can either be enabled in which case they are available for use or disabled in which case they cannot be used Disabled items appear grey rather than black For example in Figure 1 the View Edit Source button is disabled since the source type is not user defined 3 1 4 Text boxes Text boxes allow you to enter text data When you Ground Temperature K move to an empty text box an insertion point a blinking vertical cursor appears The text you type appears at the insertion point Each text box is accompanied by a caption which explains the significance of the text in the box Here it is the temperature of the ground in kelvin Text boxes which cannot be edited appear dimmed 3 1 5 List boxes LNG with nitrogen r List boxes allow you to choose one item from a list of choices The list box shown allows you to choose a liquid for the simulation This is a drop down list box so it normally appears as a rectangular box con
5. Internal error These errors should not occur in normal use of LSMS Error in number of modules with An internal error occurred while the output file was being written scalars ERROR Incorrect number of fields An internal error occurred while the output file was being written ERROR in indexing of An internal error occurred while the output file was being written 49 Wi Section 8 The LSMS files 8 The LSMS files This section lists the files which make up the LSMS installation and gives some explanation of what the purpose of each file is The files are divided into four subsections 1 programs 2 data 3 help files and 4 resources 8 1 Program files FILE DESCRIPTION LSMS EXE The LSMS interface Run this program to use LSMS LSMS 16 EXE The Windows 3 1 version of the LSMS simulation engine Carries out simulations L k SMS 32 EXE The Windows 95 and Windows NT version of the LSMS simulation engine Carries out simulations LIQEDIT EXE The liquid database tool Run this program to modify the database of pre defined liquids GSW16 EXE This file is required for the graph drawing module 8 2 Data files FILE DESCRIPTION LSMS INI Contains information about your LSMS environment such as your settings for the Options menu DEFAULT DAT Contains the default settings for the LSMS input values These values are read when the interface starts up and when you choose New from the File menu
6. box A curve showing the time variation of the variable is displayed in the graph and the time value pairs are shown in the list box at the bottom left of the dialogue box You can add a new pair by typing the time and value into the two text boxes then clicking the Add button or pressing RETURN To edit a time value pair once it has been added select it from the list then click the Edit button To delete a time value pair select it from the list then click the Delete button When you are specifying the flow rates it may be useful to note that the total volume to be spilled is calculated and displayed at the top of the dialogue box as shown in Figure 6 Once you have entered values for all the variables click the OK button to return to the main screen If you want to abandon your changes click the Cancel button At any time you can use the Copy Graph button to copy the graph for the current variable to the Windows clipboard You can then paste an image of the graph from the clipboard into other Windows applications e g for use in a report The maximum Froude number see a above for the definition of the Froude number for your source is displayed on the Configuration folder in the disabled text box Source Froude No Please note that the underlying assumptions in LSMS mean that a source with a high Froude number may not be modelled accurately You will be warned if you attempt to save an LPL file with a source Froude number of more than 2
7. contains the run title It contains three sections 1 Output 2 Numerical Parameters and 3 Time Resolution 4 6 1 Output This section contains a string describing the simulation Run Title It is used as the default title for any printed graphs It is an opportunity for the user to make some remarks about what is of particular importance or interest for the problem being set up e g a particular choice of one or more parameters a change in a parameter to examine its effect relative to an earlier run and so on 234 Section 4 The LSMS input data LSMS 1 0 Untitled File Run Dispersion Options Help Numerical Output Numerical Parameters Maximum No Of Timesteps 2000000 Spatial Resolution Maximum No OF Grid Points Hydrodynamics Time Resolution Coarse Resolution 4 d gt Fine Resolution Time Resolution Fast Simulation Slow Simulation Fine Control Normal A short distinctive title for the simulation Min Max Figure 15 The Numerical folder 4 6 2 Numerical parameters The default numerical parameters should not need to be changed in normal circumstances The Maximum No Of Timesteps textbox is used to prevent the execution time of a simulation from being excessively large If the simulation has taken more timesteps than this number without reaching the end of the specified duration it is terminated The default value is 2 000 000 If you
8. given in the Liquid Viscosity kg m s textbox and the molecular diffusivity of the vapour in the Molecular Diffusivity m2 s textbox The Antoine coefficients are defined through the correlation for saturated vapour pressure as a function of temperature log p A BAT C In LSMS the first Antoine coefficient A dimensionless is eliminated by imposing the condition p T oi1 Pa the atmospheric pressure so that the resulting expression is log PPa B T Tpoi T OC Toit C Finally enter the molecular weight in the textbox Molecular Weight g mol To add a new component to the current liquid choose Add from the Components menu To delete a component open the folder for that component and choose Delete from the Components menu To rename a component open the folder for that component and choose Rename from the Components menu You will be prompted to alter the name of the component 48 Wi Section 7 LSMS Error Messages 7 LSMS Error Messages This section lists the error messages and warnings which can be generated during a simulation with a brief explanation of each one and where appropriate some suggestions for remedial action These messages appear on the screen during execution and are also included in the log file ERROR MESSAGE INTERPRETATION Filename not specified correctly on the Either no LPL filename was passed to the simulation engine or the command line filename was not valid Unable to open
9. logarithmic scale to the x axis the y axis or both e The Data folder allows you to view the values for the first 100 points of the graph e The Axis folder allows you to choose whether to have a grid in the background of the graph by checking Show in the Grid section Users should not attempt to alter the range of the axes here they should use the Graph Axes dialogue box instead see Section 5 4 2 below e The Fonts folder allows the user to alter the fonts which are used for the text elements of a graph e The Markers folder allows the user to alter the line style and markers used to display the data e The Background folder allows borders and backgrounds of various styles to be added to the elements of the graph There is extensive on line help for this dialogue box to which users are referred if they wish to experiment with it in more detail 235 ED a Section 5 Plotting the results 5 4 2 Using the Graph Axes dialogue box Axes Peositon n Cancel Minimum DER Maximum gt Dil Ticks lt Axis Total Height m Minimum Y Maximum Y Ul Ticks Y Axis Figure 25 The Graph Axes dialogue box Select the Graph Axes button on the Plot folder to reach the Graph Axes dialogue box which controls the ranges of the axes This dialogue box is shown in Figure 25 for a snapshot of total height against position It allows you to set the maximum and
10. minimum values for each axis and the number of subdivisions ticks between zero and the maximum value Users should bear in mind that all the graphs in a particular display type will then have the same x axis a change made to one graph will affect all the others 5 5 Printing graphs Once you have produced a set of graphs you can print them to any printer supported by Windows To print the current set of graphs select the Print Graphs button on the Plot folder or choose the Print Graphs option from the File menu This displays the Print Graphs dialogue box Figure 26 Note all the graphs which are being viewed on the Plot folder are printed as a set i e all the display types variables and frames will be printed together Before printing graphs users should check which graphs are included in the current set by means of the list boxes at the top of the Plot folder otherwise they may produce unwanted printed output 36 Ec m Section 5 Plotting the results Print Graphs x Page Appearance 12 M No of graphs on a page X Add border round each graph Cancel X Use white background for graphs Printers it X Show print details in footer X Show title on each graph Page Title Current Graphs potou un ra Printer Type C Colour pu Black and White Figure 26 The Print Graphs dialogue box The Print Graphs dialo
11. the angle that the ground makes with the horizontal The slope is assumed to be uniform Positive slopes indicate that the slope runs downhill from the source 4 3 2 Homogeneous porous substrates This option represents a solid porous homogeneous substrate The liquid can seep into the substrate allowing heat transfer directly from the porous matrix to the seeped liquid contributions from conventional conduction as well as convection are also included The temperature of the ground before the spill Ground Temperature K must be specified this is also the temperature of the ground far from the surface at all times during the spill The thermal properties of the substrate are the properties for the entire porous medium in situ i e without attempting to separate out the solid matrix from the pores or their contents and they are specified in the Thermal Conductivity kW m K Thermal Diffusivity m s Specific Heat Capacity kJ kg K and Density kg m textboxes The four values are coupled see Section 4 3 1 Use the Slope textbox to enter the tangent of the angle that the ground makes with the horizontal The slope is assumed to be uniform Positive slopes indicate that the slope runs downhill from the source You can use the Change Porous Properties button to view or edit the porous nature of the substrate This displays the Porous Properties dialogue box the basic version of which is shown in Figure 10 The advanced version gives t
12. use Timestep Multiplier 0 125 O0 lt x lt 2 Only available if Modify timestep during run is during the run checked Timestep number after Use After Step 1000 0 lt x 10 000 000 Only available if Modify timestep during run is which the multiplier should be used checked 64
13. 02 9030689 0 900187 1 04795 3296396 8 921544E 02 Figure 35 The SPL file format Tabulated properties of the overtopped liquid Note that the flow rates stored in this file represent the spillage over the entire bund perimeter in the primary spill If a simulation is carried out for a secondary spill for which the geometry is different to that of the primary domain the flow rate is adjusted appropriately during the simulation see Section 4 1 1 c 53 od A Section 9 Files produced for each problem 9 3 The format of the user defined source file It may be useful to know the format of the user defined source file SRC file for example users could write programs to generate their own source files if they required the source to fit a certain functional form See Section 4 1 1 for details on entering user defined sources using the interface For a user defined source the user defines the time variation of flow rate temperature and composition of the incoming liquid by giving the value at a set of times for each variable LSMS uses these to calculate the value of each variable for the current simulated time assuming that the values vary linearly between pairs of data points and remain constant at the last value once the last time is passed The SRC file is a text file which contains a list of time value pairs for each variable defined The overall structure of the file is shown in Figure 36 a The file is divid
14. 1 4 63 POOL T Section 10 Summary of input parameters Parameter Interface Default Range Type Notes NUMERICAL cont Minimum height surface Surface Tension Height m 0 003 m 0 lt x lt 0 1m Only available if Surface Tension chosen The tension effects value would be expected to increase with roughness 0 003 m is appropriate for average roughness Note that this parameter must be greater than the minimum depth for the pool Turbulent drag coefficient Turbulent Drag 0 003 on water 0 x 0 05 Note that the default depends on the substrate chosen It should be noted that LSMS is more 0 01 on land M sensitive to this parameter than to any other advanced parameter The value could be varied to reflect the roughness of the substrate but only with caution Include viscous shear Include viscous shear stress Checked If this effect is included the value of the kinematic stress viscosity of the liquid is used Minimum depth for the Dry out depth m 1x10 m 0 lt x lt 0 01m The pool is deemed to have vanished at a point pool once the depth there falls below this value Whether the time Modify timestep during run Unchecked Use this facility to fine tune modification of the resolution should be timestep during the run This allows the time modified during the run resolution to be altered at any point during the run not just at the start Timestep multiplier to
15. 11 The Porous Properties dialogue box advanced version Use the Grain Size m textbox to enter a representative diameter for a grain in the porous medium It will be used to provide an estimate of the size of bubbles of vapour in the substrate Use the Conductance s textbox to specify the parameter used to characterise the heat flux from the porous medium into the liquid in the pores Its value depends on properties of the porous medium and needs to be found from experimental correlations although a simple estimate assuming spherical grains and perfect thermal contact between the liquid and the matrix suggests that it could be of the order of 0 1 10 s The default value of 1 s is typical The relative permeability scale Rel Permeability Scale in the dialogue box is a scale factor used to determine the dependence of the volume fraction of liquid in the porous medium and hence the relative permeability of liquid seeping into a porous medium on the rate at which the liquid is being turned into vapour Its value needs to be determined by experimental measurements of simultaneous seepage and boiling of a liquid cryogen in a porous medium The default value of 0 25 is considered representative for a cryogen Users are referred to the L MS Final Report for more details on these parameters LiPSOL users should note that the relative permeability scale in LSMS is defined differently to the LiPSOL parameter with the same name 4 3 3
16. 4 1 2 Geometry There are two geometries available for LSMS runs namely axisymmetric and planar and the geometry is chosen using the Axisymmetric and Planar radio buttons Axisymmetric geometry means that the spill has cylindrical symmetry Planar geometry means that the flow is unidirectional as if contained within a parallel sided channel and uniform across the flow The spill width in the transverse direction must be specified Domain Width m 4 1 3 Simulation span The simulation will continue until all the fluid has vaporised or until the maximum duration of the simulation is reached Duration s It may be advisable to begin with smaller values of the duration say 10s 100s to get some idea of the behaviour of a particular case if this is uncertain before extending it to longer runs This avoids having unnecessarily long computations and output files for all the examples examined The Output Interval S textbox is used to give the time interval between successive output of the state of the spill to the main data file Generally this should be between 0 1 and 1 of the simulation duration to avoid the output files becoming too large Users should also bear in mind that the smaller the output interval the slower the simulation will be On the other hand a smaller output interval records the evolution of the spill with time in more detail 15 KG Section 4 The LSMS input data 4 2 The Liquid folder The Liquid folder co
17. 755134 1 000 74 508 5619 88 57378 111 708 1 75494 1 000 78 521 1422 90 74412 111 7067 1 754216 1 000 82 533 8445 92 85405 111 7056 1 754455 1 000 86 546 1724 94 90705 111 7045 1 75428 1 000 90 557 8319 96 90535 111 7034 1 754338 1 000 94 569 1727 98 86556 111 7025 1 753974 1 000 98 579 8741 100 7949 111 7015 1 75395 1 000 Figure 31 An example generic dispersion file 6 3 Running lists of problems LSMS has the facility to run sets of problems consecutively which is useful if the user has a set of lengthy problems and wishes to run them all as one operation Before using this facility you must create a list of problems The lists are stored in files which usually have the extension LST 44 Cod Section 6 Further features 6 3 1 Creating a list of problems Select Edit List from the File menu This will display the dialogue box for creating and editing lists of problems Figure 32 List File lt untitled gt Choose files to add to list Current list P c projects Isms tests feb94 gqdf3c Ipl e MARK S DISK p c projects Isms tests feb94 gqdf4_Ipl Path c lsms tests feb94 E c E projects gt Isms 7 feb94 graphf 1 C3 saved gd 3c Ipl d 4 ipi Add To List pen List File Save List File As Clear List Close Figure 32 Dialogue box for creating and editing lists of problems e The Current list section at the centre of the dialogue box show
18. CURSOR will move the cursor up through the radio buttons for the current item T CURSOR Mire will move the cursor down through the radio buttons for the current item In general if a letter in the name of an interface item is underlined then pressing the ALT key with the key for that letter will trigger that interface item For example the File menu has the letter F underlined on the screen as shown in Figure 1 Pressing the ALT and F and together will open the menu foo A Section 3 Basic use of LSMS 3 2 An outline of LSMS The LSMS interface is divided into seven tabbed folders These tabbed folders allow easy access to all input parameters To swap between folders use the mouse to click on the name of the folder you want to reach The folders are Configuration This describes the overall characteristics of the spill It has three subsections a source type b geometry and c timings This describes the liquid used in the spill and its initial conditions Substrate This describes the form of the substrate onto which the spill has been made Atmospheric This describes the aspects of the atmosphere which affect the spill Bund This allows specification of a bund and its properties Numerical This describes aspects of the numerical solution of the governing equations It also contains the title for the run Plot This allows the user to produce graphs of the results of a simulation Each LSMS case is identified
19. LSMS 1 0 USER MANUAL Project FM 140 95 26 November 1997 Cambridge Environmental Research Consultants Ltd 3 King s Parade Cambridge CB2 1SJ UK Tel 44 0 1223 357773 Fax 44 0 1223 357492 E mail Isms cerc co uk Table Of Contents Mireille 1 Ei Themod l EXPE 1 1 2 Comptteramplementath om sic a eee tope ea e ERE E E E EE aE OO E a E HER HE EERS 1 13 Other documentation Ln ea ae de ec e cede ad oe ER e ARR Gee le 1 2 Getting StALted d 2 2 1 Document structure and conventions eeecceecceesteceesseceeececeseeessaeceeaeeceeeecaeceeaaeceeaeeceeeeeaeceeaeeseeeens 2 2 2 Minimum system requirements one eed tete e diee ped etta ee ra eee ge nh eee eee eed oa ea erae dade ea ege 2 2 3 Installing nd star umng ESMS iei iecete eet iere segues este t tee i eU bed e eH Rete eee io adea 2 23 1 JInstallatiOmoc s etc Nette ettet eite ett o tette decessores 2 23 2 Startins LSMS cece D 3 RE ASIC USE OL LSMS T M 4 Sel General Windows feat res atii ici estt tet oggi to tete Hp et LHP REEL ERE RE Ee Ge eL EE AE 4 34b TG MENU DA is Re DO oe pete e he IU OU a RE A PRSE S 4 321 2 The help Dare oon De tede ceret E AER OC ERE SEE OE v etre 5 3 1 3 Enabled and disabled items ete e ete eren e ade Xe IRE dre eh de E eR ve 5 S3 MEMFO SUCI M 5 3 1255 List boxesss sene RU RUE ederet e tere eite epp usps bete eve re
20. OES 5 3 1 6 CheckbDOX6S eee tiet rre eee ee eerie er e e ede eee le ee et eer ese ede e Ua 5 Slee Rado buttons e eee eee nto RH ER ca ER Me e REN I E aTe 5 3 1 8 Command buttons inerte tette tree HI et he eMe RR eO deret tob Coe aeg ea bod eoe ETE Reed 6 3 1 9 Spin buttons ue THERE p o EP EUER eere HR ET HR ee Lee etui 6 9 110 Dialogue DOXES 2 derer tee ete e Cre an Er e Tee uet eet 6 3 1 LI Message boxes si ee eis tiene eae ieee Wo nil ee E T t EA 6 3 1 12 Navigating using keyboard iie tet heme eed ce Lia ee ede tede e dtc 7 3 2 An outline Of D SMS sen ind nie p BA ss dh ep A eere ease edge A edad eas 8 9 2 1 STS PIS menu erbe eere be HR te e eee beatae Hie ee Poe T ee 9 3 2 2 The Run eni e E CO RARE A RENE E BRE EUER EYES ER REOS 9 4 The PdukSmimbirem M 10 4 1 The Configuration folders 5 iier eere eet eni erectos tei t tete i eee ete et ro ee REOR Roe 10 4 1 1 Source types and dimensions ii sesetee ente thee tne theo eet toten ratore te cia 11 CERE GUN DM E 15 S SN EE Inline 15 42 The Liquid folder igo x Ro qe ERAS 16 42 JVFaquid type eet cette tee Ee EE nee RIT I 16 ADD Inrtialstate 5er n esee eileen tht ten rote ioo atest 16 4 2 3 Bubbles uei etd ete este e Re tet Le ite ta RE edet p cte tp pe n etie end 17 4 3 iThe Substrate folders i ee ER e odes ev e dee nl iad clas ER YER Gum EURO ede oak 18 4 3 1 Homogeneous impermeable substr
21. The liquid name is specified as one of its properties e Export allows the liquid database to be saved to a text file in tab delimited form It can then be loaded into a spreadsheet e Exit closes the liquid database tool 6 5 2 Entering a liquid s properties Figure 34 shows the liquid database editor with a predefined liquid loaded This liquid is LNG taken to be a mixture of methane and ethane Note that the composition is not set in the database but is set for each LPL file using the Liquid folder see Section 4 2 At the top of the screen is the Name text box where the name of the liquid should be entered Next to this is a label indicating when the liquid was last modified The properties of the individual components are displayed on tabbed folders like those for the main LSMS interface These properties apply to the liquid phase except for the molecular diffusivity of the vapour Molecular Diffusivity m s In general if any properties vary with temperature values for some typical spill temperature should be used i e the lower of the boiling point of the liquid and a typical ambient temperature e g STP You should enter the density and boiling point of the liquid Liquid Density kg m and Boiling Point K The specific heat capacity of the liquid should be entered in the SHC kJ kg K textbox and the latent heat of vaporisation in the Lat Heat Vap kJ kg textbox The viscosity of the liquid should be
22. Two layer substrate A two layer substrate is a solid substrate made up of two impermeable layers which transfers heat into the spill by conduction Typically the upper layer is insulating relative to the base layer The temperature of the ground before the spill Ground Temperature K must be specified this is also the temperature of the ground far from the surface at all times during the spill The thermal properties of both layers of the substrate must be entered The thermal properties Thermal Conductivity KW m K Thermal Diffusivity m s Specific Heat Capacity kJ kg K and Density kg m of the lower layer i e the main bulk of the substrate are set on the main Substrate folder itself These four parameters are coupled see section 4 3 1 The properties of the upper layer can be set or viewed by clicking the Change Upper Layer button This displays the Upper Layer Properties dialogue box see Figure 12 220 KG Section 4 The LSMS input data Upper Layer Properties x Upper Layer Properties Layer Depth m Thermal Conductivity Kw m K 00144 Thermal Diffusivity nts Specific Heat Capacity kJ kg K Layer Density kg rr Cancel Thickness of upper layer in m Min 0 Max 1 Figure 12 The Upper Layer Properties dialogue box The upper layer thickness is entered in the Layer Depth m textbox The thermal properties of the upper layer are entered in the text
23. WI2 LPL File Bun Dispersion Options Help Frame Display Type p Multiple Frames Plot Variables E 4 E 3 lel a 09 x ee Pnnt raphs Load Graphs Save Graphs lear Graphs Iaraphi5tyle Graph Ares Inquire Save Data Select the data to be plotted Figure 20 The Plot folder Having successfully completed a simulation the user will want to examine the output produced and display the results graphically The Plot folder allows the user to do this There are four types of graph which can be produced time series snapshots totals and averages e Time series are plots of the time evolution of a quantity at a particular location e Snapshots are plots of the spatial distribution of a quantity at a particular time e Totals are graphs of the time evolution of properties summed over the whole pool e Averages are plots of the time evolution of properties averaged over the whole pool Time series can be produced for a set of positions and snapshots can be produced for a set of times In LSMS each individual graph in a set like this is called a frame In addition to producing graphs the user can interrogate the data file and display the numerical values of the properties of the pool at a particular time and place see Section 6 4 2205 Ec m Section 5 Plotting the results 5 2 Selecting data to plot Select Data Display Type Variables Time series x Int
24. WINS PTapbs iine e e ee ge e ERA Led etie te bae a Ee HO ORE e sede at Pete tecaetebeh cones 34 5 4 Customising graphs o Re ea 35 5 4 1 Using the Graph Style dialogue box esee nnne eene 35 5 4 2 Using the Graph Axes dialogue box sees nee 36 5 5 Prin ng Graphs oim td eet e e Ee te E Re ele ta RE Deas cae tp ee RE eie ed 36 5 6 Saving and loading eraphis aea dee c ate ete ee RR eed ia 38 217 COPY PTaplsca 5o et nee eate tee edet pere et ihe e ti eee etel 38 5 8 Clearing graphs uet et Ee eere EIE GIRO E E n E rete reed caw HEURE e ee LT wei ERR eden 38 5 9 Exporting graph data to a spreadsheet sese nennen entrent 38 6 Further featUres MR TU 39 o ME O 81510 1 KE sie dece ie re E E 39 6 1 1 Thernaldiffusivity Opt ons 21 oe re eet repe lee ertet ipeo a a a etes 39 6 1 2 Including problem summaries with printouts eee eeseceseceseceeeeseeeeceeeseeeaeecaaecaecsaecnseenseeess 39 6 1 3 Prompting for run titles at each save oo eee esse ceseceeceseceseceseeeseeeseeeeaeecseecaeecaaecsaecaecaecnaeeseeees 40 6 1 4 Automatic notification when simulations terminate eese nennen 40 6 1 5 Choosing the 16 bit or 32 bit version eene nnne ennren rene enne nnne 40 6 1 6 The advanced features of the interface sess ener enr en rennen 40 6 1 7 Simulation run time graphics eese enne ener enr en rennen nenne 40 6 2 Linking to dispersion m
25. and allowed range are given for each one with some brief comments on the significance of the parameter and under which circumstances it should be varied from the default The input items which are typically different from case to case and so need the most attention are marked with an asterisk in the Type column Parameters which are relevant for certain main options only for example solid substrates or secondary sources have a comment to this effect in the Notes column Users are reminded that there is a more detailed discussion of the input data in Section 4 Each parameter occupies one row of the following tables The information contained in each column is outlined below Parameter A brief description of the parameter Interface The interface textbox or other component through which the parameter is specified Default The default value for the parameter The parameter is set to this value when you choose New from the File menu Range The range of values which is allowed for the parameter Type An asterisk in this column indicates that the parameter is typically different from case to case Notes Any special points which should be taken into consideration 55 Ec T Section 10 Summary of input parameters dimension for source Source Position m or Source Length m Parameter Interface Default Range Type Notes CONFIGURATION Source t
26. atabase editor LSMS is distributed with a database of predefined liquids which can be edited using the tool LIQEDIT EXE This has been implemented as a separate program since it will probably be used infrequently and this also allows administrators in a multi user environment to control access to the database To prevent less experienced users from altering the database simply remove LIQEDIT EXE from their LSMS installation Note that the files containing the liquid properties are automatically stored in the data subdirectory of the LSMS home directory l LiPSOL Liquid Database Liquid Components Name Last modified 06 10 97 10 42 Methane Component Properties Liquid Density kg m Liquid Viscosity ka m s Boiling Point K Molecular Diffusivity m s SHC kJ kg K Antoine B Coefficient K Latent Heat Vap kJ kg Antoine C Coefficient K Thermal Expan K Molecular Weight g mol Name of the liquid Figure 34 LSMS liquid database editor 47 fod Section 6 Further features 6 5 1 The Liquid menu The Liquid menu allows new liquids to be created and existing liquids to be modified or deleted e To create a liquid from scratch choose New e To open an existing liquid choose Open and choose the liquid from the list m displayed Pun e To delete an existing liquid choose Delete and choose the liquid from the list displayed Export Exit e To save the current liquid choose Save
27. ates esses nennen nennen nennen enne 18 4 3 Homogeneous porous substrates esee neret nnne netten 19 4 3 3 Two layer substra te 2 tonitru e ea eet Lo e RE EEEE 20 ASA Spills om Water e ae RISE UN EE ehe 21 44 ThesAtmosphetic folder 2 5 dre eee eerte EE te ree e rte 22 ANS The Bund folder asurre r item ER Pen EE ePi aude EEE eoY ve Enea 23 45 l Bund treatment ien eee oet ete et De etl re eti e E eg t oer estes 23 4 5 2 Bund Gimensions yee eis ne Ro e e t RE eot p ei esten Bree OP E ERE tenses 24 4 5 3 Bund wallthermal properties x ccc ee repete eie ere ttt get e ete et ere getggt 24 4 6 The Numerical foldet ierit rre cerei ete E Re teet ree Reit 24 LONE Gb ER EE 24 4 0 2 TNumirical parameters a eR E ee e de i e a RETES 25 4 6 37 ime TESOL OM erie 2e ttt terere teris hec E RU Pe ENTRE EE EIE REPEAT laces EN Td CY EROS 26 S Plotting the results 55 neret eo rre repr eot P Pee EE ea Ea eco teg eae ep rao EF oe pa ee e rep eo oa PE EE spado se re sabesteenssosenesses 29 Table Of Contents 5 Plotting overview uei ER eb eie Eee nrc a etn aede COD a ota 29 52 Selecting data to plot ee LR ERE es ee red Ee ee ee S 30 5 2 1 Selecting equally spaced trames edge ete ditate eene este ete bi et ee e 31 2 2 2 Selecting Custom frames edet ee E a E a ete caet tid techie eh leat ale RE 31 5 2 3 Variables which can be plotted seen 32 25 3 WAC
28. boxes labelled Thermal Conductivity KW m K Thermal Diffusivity m s Specific Heat Capacity kJ kg K and Layer Density kg m3 These four parameters are again coupled see Section 4 3 1 Use the Slope textbox to enter the tangent of the angle that the ground makes with the horizontal The slope is assumed to be uniform Positive slopes indicate that the slope runs downhill from the source 4 3 4 Spills on water If a spill occurs on water heat is transferred to the liquid from the water below at a fairly constant rate due to convection set up in the water If ice formation is not modelled then the heat flux is taken to be constant throughout the simulation at the value entered in the Initial Heat Flux kW m textbox To model ice formation during the spill check Ice Formation In this case the heat flux from the water to the liquid will start at the value entered in the Initial Heat Flux kW m textbox and decay exponentially to the value shown in the Final Heat Flux kW m textbox 21 KG Section 4 The LSMS input data 4 4 The Atmospheric folder LSMS 1 0 TEST 01 LPL Fie Run Dispersion Options Help Atmospheric Solar Flux kw r Roughness Height Wind Speed Profile Friction Velocity m s Smooth Rough C Custom Use reference speed and height x vil Roughness Height m JUUeco Wind Speed n s P Heat flux due to sola
29. by a main input file which has the file extension LPL In the rest of this manual they will be referred to as LPL files They contain almost all the input data needed to carry out an LSMS simulation A full description of the input data is given in Section 4 but it is worth noting that each LPL file has a text string associated with it entered on the Numerical folder and captioned Run Title It is recommended that you use this to store a brief description of each case this will help distinguish them in the future LPL files are managed using the commands from the File menu see Section 3 2 1 Simulations are carried out using the commands from the Run menu see Section 3 2 2 As the simulation proceeds it creates output files to accompany the LPL file There are various files see Section 9 1 for a complete list the most important of which are the log file and the binary data files e The log file extension LOG is a text file which contains a summary of the progress of the run e The binary data files extensions LD1 and LD2 contain the detailed output from the simulation They should only be accessed using the interface Their size depends on the output interval and simulation duration for the case being run but they can be quite large If disk space becomes short it is a good idea to delete or archive binary files from past simulations If the LPL and SRC files are kept the simulation can always be repeated later When the simula
30. cal Size m of the source if you wish or alternatively the vertical size of the source can be calculated during the simulation To set the vertical size explicitly check the Specify Vertical Size checkbox The Froude number for your source is displayed in the disabled text box Source Froude No Please note that the underlying assumptions in LSMS mean that a source with a high Froude number may not be modelled accurately You will be warned if you attempt to save an LPL file with a source Froude number of more than 2 Figure 4 a gives schematic representations of continuous sources for axisymmetric and planar geometries the horizontal dimension is xo the vertical size of the source is h and the volume inflow is V b Dambreak source This represents an instantaneous source in which a volume of liquid is suddenly released from rest You must specify the size of the initial volume of liquid For an axisymmetric geometry this volume is cylindrical and you must give the radius Source Radius m and height Vertical Size m For a planar geometry the initial volume is cuboidal and you must give the length Source Length m and height Vertical Size m together with the width Domain Width m which is specified in the geometry section Figure 4 b gives schematic representations of dambreak sources for axisymmetric and planar geometries the horizontal size is xo the vertical size is ho and the domain width for the planar geometr
31. decide when the simulation seems to begin using too large a timestep then look in the log file to find out the approximate timestep which corresponds to the onset of these difficulties Now open the Advanced Numerical Parameters dialogue box and check the Modify timestep during run checkbox Enter the timestep number in the Use After Step textbox Enter a value in the Timestep Multiplier textbox of less than 1 and press OK Save the LPL file under a new name and run the simulation 26 od a Section 4 The LSMS input data Advanced Feature You can select the Hydrodynamics button to access some of the parameters controlling the simulation of hydrodynamic aspects of the spill It is recommended that the default values for these parameters should be used for most simulations and that the LSMS Final Report should be consulted before they are changed The button launches the Hydrodynamics parameters dialogue box Figure 18 Hydrodynamics parameters Lx Front Treatment R z Front Parameters Constant Froude Number Basic ic Froude INS Surface Tension Surface Tension Height m Hydrodynamics Parameters Include viscous shear stress x Cancel Figure 18 The Hydrodynamics parameters dialogue box The Front Treatment radio buttons allow you to specify the treatment of the front in the hydrodynamics calculations If Constant Froude Number is chosen the front has a constant Fr
32. ds back through the list by clicking the up arrow with the mouse Correspondingly you move backwards up through the list by clicking the up arrow with the mouse 3 1 10 Dialogue boxes Dialogue boxes are floating screens which appear when you need to supply additional information to complete a task An ellipsis after a menu command indicates that a dialogue box will appear when you choose that command For example if you choose the Open command on the File menu the dialogue box shown in Figure 2 will appear In this dialogue box you specify the name of the file you want to open You choose the OK button to open the file you have chosen You choose the Cancel button to close the dialogue box without opening a file Several other dialogue boxes have OK and Cancel buttons Cancel will always close the dialogue box and discard any actions or input made in it whereas OK will accept any input from the dialogue box and carry out any appropriate action amp Open ix File name Folders c projects Isms tests Cancel 1comp Ipl ec 2comp Ipl y projects 3c bndov Ipl Network dii 3comp Ipl 2 Isms bund ipl Sy tests cst 2ry lpl EI 2ry Read only default ipl instkwi2 Ipl List files of type Drives Input files LPL amp J c mark s disk Figure 2 The dialogue box for opening files 3 1 11 Message boxes Message boxes are a particular type of dialogue box They may give you a brief message o
33. e downhill from the source horizontal Modify this value to model a sloping site Initial constant heat Initial Heat Flux kW m 50 kW m2 0 lt x lt 1000 Spills on water This is the constant value flux kW m used when no ice formation modelled Whether effect of ice Ice Formation Unchecked Spills on water formation on heat flux is modelled Final heat flux Final Heat Flux kW m 25 kW m 0 x 1000 Spills on water with ice formation This kW n value must be less than the initial heat flux 59 m Section 10 Summary of input parameters Parameter Interface Default Range Type Notes SUBSTRATE cont Absolute Permeability m 1x 10 m O lt x lt l Porous substrates This parameter can be Permeability measured but in practice is often poorly known Porosity Porosity 0 4 O lt x lt l Porous substrates This parameter can be measured but in practice is often poorly known Depth of porous layer Porous layer depth 1000 m 0 lt x lt 1000 m Porous substrates If the porous layer is effectively infinite use the default value Grain size Grain size m 0 01 m 0 xx0 1 m Porous substrates It is recommended that the default value is used Relative permeability Rel Permeability S cale 0 25 0 lt x lt 1 Porous substrates It is recommended that the scale default value is used Conductance Conductance s 1 s 0 lt
34. e friction velocity directly or to give a measured wind speed To give a measured speed check the Use reference speed and height check box You should then supply a measured wind speed and the height at which the measurement was made using the Wind Speed m s and Wind Height m textboxes respectively The friction velocity will be calculated from these values 4 5 The Bund folder LSMS 1 0 TEST 01 LPL Fie Run Dispersion Options Help Bund Treatment Bund Dimensions Bund present x 0 Bund Radius m Model overflow x Bund Thickness m n e Bund Depth m B Bund Wall Thermodynamic Properties Thermal Cond Kw m K 00144 Density kg m 2323 Thermal Diffusivity ns 4 920E 7 Specific Heat Capacity KJ kg K Check to include bunds in the simulation Figure 14 The Bund folder The Bund folder controls the specification of any bund present There are three Sections 1 Bund Treatment 2 Bund Dimensions and 3 Bund Wall Thermodynamic Properties 4 5 1 Bund treatment The most important decision on this folder is whether or not to include a bund in the simulation To include a bund check the Bund present checkbox If this is not checked the other controls on the folder will be disabled You can also choose whether to model the evolution of any liquid which overtops the bund wall The simulation will proceed faster if you do not model the overtopped fluid i
35. e in which the flow rate temperature and composition of the inflowing liquid vary throughout the spill As for a continuous inflow source you must also specify the source dimension In an axisymmetric geometry you give the Or both domains are axisymmetric but the secondary domain is a sector whose boundaries are not radii of the primary domain see the lower right part of Figure 5 e T3 KG a Section 4 The LSMS input data source radius Source Radius m which is the radial distance from the origin at which you specify the volume inflow i e the flow rate is the volume of liquid per unit time crossing the surface at x source position In a planar geometry you give the x co ordinate of the source Source Position m which is the distance from the origin at which you specify the volume inflow You may also specify the vertical size of the source Vertical Size m if you wish or alternatively the vertical size of the source can be calculated during the simulation see footnote 2 above To set the vertical size explicitly check the Specify Vertical Size checkbox Figure 4 a gives schematic representations of user defined sources for axisymmetric and planar geometries the horizontal dimension is xo the vertical size of the source is ho and the volume inflow is V User defined source debe Total Spill m n l Stop Time s Current Values Time s Fowrtetmz Edt Delete nn
36. ed into sections marked by text strings in single quotation marks FLOWRATE TEMPERATURE and CONCENTRATION The flow rate and temperature sections are both simply a list of time value pairs The concentration section begins with an integer indicating the number of concentrations which are to be specified this will be one less than the number of components in the liquid Then follows the lists of time concentration pairs The format of a time value list is shown in Figure 36 b Each list starts with an integer which is the number of time value pairs in the list It is important to note that there cannot be more than 250 pairs in any list Next follow the time value pairs sorted into ascending order by time Each pair occupies one line and consists of a time then a comma then the value FLOWRATE n Time value list for flow rate Time Value TEMPERATURE Time Value Time value list for temperature CONCENTRATION Timen 1 Valuen 1 N 1 Time Value Time value list for component 1 Time value list for component 2 Time value list for component N 1 a Schematic outline of SRC file format b Schematic outline of a time value list Figure 36 SRC file format 254 Wi Section 10 Summary of input parameters 10 Summary of input parameters This section contains a brief summary in table form of all the input parameters which may need to be specified when setting up a run with LSMS The default values
37. ed values can be removed from the list by double clicking them with the left mouse button If you are producing custom frames for snapshots the Select button will display a dialogue box similar to that shown in Figure 23 Snapshots will be generated for each time in the listbox Current values You can add new times to the list by entering a value in the Next time s textbox then pressing the sPACEBAR Unwanted values can be removed from the list by double clicking them with the left mouse button 5 2 3 Variables which can be plotted This section defines the output variables from a run of LSMS which can be plotted 5 2 3 1 Variables which are available for time series and snapshots These variables are available both for snapshots and time series They all represent local values at a specific position in the pool and a specific time Note that variables marked with a common superscript are alternative versions of the same variable the Units radio button on the Plot folder may be used to toggle between length based and mass based units Interface height m The depth of the pool For spills on water the position of the upper and the lower interfaces will be plotted on the same set of axes relative to mean sea level For spills on porous substrates the seepage depth and the depth of the pool above ground will be plotted on the same set of axes Mass per unit area kg m2 The local mass per unit area For spills on porou
38. erface height m Snapshots Cancel Totals x Velocity m s Averages Range t x Methane conc x Ethane conc Concentration 3 Units Use length based units C Use mass based units x Methane vapour conc Frame Selection x Ethane vapour conc Selection Method Gei Vapour concentration 3 Equi spaced i qui spaced X Temperature K C Custom X Vaporisation rate mm s ENIM x Position m X Void fraction Produce a set of equally spaced frames Min Max Figure 21 The dialogue box for selecting data to plot To produce a set of graphs select the Select Data button on the Plot folder Figure 20 This will display the Select Data dialogue box Figure 21 This dialogue box is used to specify the graphs which are to be produced as explained below First use the Display Type listbox at the top left to choose the type of graph to generate either time series snapshots totals or averages Next choose the variables which are to be plotted by selecting the relevant checkboxes in the Variables section of the dialogue box For time series and snapshots the Units for some variables can be altered If you choose Use length based units you can plot pool height in m the velocity in m s and the vaporisation rate in mm s If you choose Use mass based units these variables are converted into mass based equivalents i e you can plot the mass per unit a
39. f necessary you can model the evolution of the overtopped fluid later by creating a secondary source see Section 4 1 1 c However it should be noted that the overtopped fluid will be modelled more accurately if 2235 LD m Section 4 The LSMS input data it is included in the primary spill To include the overtopped fluid in the primary spill check the Model overflow checkbox 4 5 2 Bund dimensions This section allows you to specify the dimensions of the bund The geometry of the bund is assumed to be the same as the geometry of the spill specified on the Configuration folder see Section 4 1 2 Use the Bund Radius m textbox to enter the distance from the origin to the inside of the bund wall the inner radius of the bund Notice that when the ground is sloping this is the distance to the bund wall along the ground Use the Bund Depth m textbox to enter the height of the bund wall assumed perpendicular to the ground and the Bund Thickness m textbox to enter the thickness of the bund wall i e the outer radius minus the inner radius 4 5 3 Bund wall thermal properties This section specifies the thermal properties of the bund wall material namely thermal conductivity thermal diffusivity specific heat capacity and density These four parameters are coupled see Section 4 3 1 4 6 The Numerical folder The Numerical folder see Figure 15 describes aspects of the numerical solution of the governing equations and also
40. f the files produced for each problem considered eee 52 9 2 The format of the spill tile ee eter ente the erste treten e reed 53 9 3 The format of the user defined source file eene 54 10 Summary of input parameters 4 eee eres eere ee esee ee setae enean stone tone ettet sesto sese sete seas e ea seen setas tas enata ae 55 1V Wi Section 1 Introduction 1 Introduction 1 1 The model A spill and subsequent vaporisation of a liquid cryogen or volatile caused by the failure of a containing vessel presents a potentially serious hazard to the gas industry Liquids such as liquefied natural gas LNG liquefied petroleum gas LPG and others are routinely stored at low temperatures and on their release to the atmosphere they boil or evaporate depending on their temperature relative to the ambient air Such liquids flow across the ground or other substrate surrounding the containing vessel extracting heat from the underlying surface which provides the energy to drive the vaporisation As the liquid spreads the size of the liquid pool changes and the vaporisation rate alters accordingly and such information is essential for calculating the subsequent dispersion of the cold vapour In many circumstances the containing vessel is surrounded by some mitigating measure such as the presence of a bund and the flow of the liquid and its interaction with the bund wall presents a formidable predict
41. gue box allows you to specify how the graphs will appear on the printed page The number of graphs i e sets of axes which will be printed per page is set by the No of graphs on a page listbox at the top left of the dialogue box The text entered in the Page Title textbox will appear at the head of each page of graphs The default title is the run title of the simulation The font size for the page title is set in the text box Font Size Point The Printer Type radio buttons should be set to either Colour or Black and White depending on the printer to be used The printer can be changed or its settings altered by selecting the Printers button Check Add border round each graph to apply a box border to each graph Check Use white background for graphs to give each graph a white background Check Show print details in footer to include details of the filename and date of the printout at the foot of each page Check Show title on each graph to include a title with each graph This is not the same as the page title The Current Graphs section lists the graphs which have been generated The number of variables and frames in each display type are shown This reminds the user how many graphs are being printed 2375 fod m Section 5 Plotting the results 5 6 Saving and loading graphs Once a set of graphs has been produced it can be saved for later retrieval This facility may be useful for graphs which may be needed later for
42. has a list of the positions or times which were generated and you can use it to swap between them Alternatively you can use the spin buttons next to it to move through the list of frames Multiple sets of frames can be displayed on one pair of axes by checking the Multiple Frames checkbox The number of frames which will be displayed at one time is set in the No Frames text box Note that if an item from a list box is selected as for example Interface height is selected in Figure 24 then the 7 CURSOR and CURSOR keys can be used to move backwards and forwards through the list In the case of the Frame list selecting the first frame in this way and keeping the key de fod m Section 5 Plotting the results depressed in effect animates the display which can be instructive in demonstrating the evolution of the pool shape when the frames are equally spaced snapshots 5 4 Customising graphs There are two buttons on the Plot folder which allow you to customise the appearance of your graphs the Graph Style button and the Graph Axes button Both display dialogue boxes which are discussed below 5 4 1 Using the Graph Style dialogue box Select the Graph Style button on the Plot folder to access the Graph Style dialogue box which gives control over the appearance of the graphs The dialogue box is divided into folders Some of the most useful aspects are explained below folder by folder e The Style folder allows you to apply a
43. he dialogue box in Figure 22 Time series will be generated for a series of positions from the minimum Minimum position m to the maximum Maximum position m separated by the interval which you enter Interval m If you are producing equally spaced frames for snapshots the Select button will display a dialogue box similar to that shown in Figure 22 Snapshots will be generated for a series of times from the minimum Minimum time s to the maximum Maximum time s separated by the interval which you enter Interval s 5 2 Selecting custom frames Enter custom positions for time series 20 Cancel Press the spacebar to insert the next position Min 67 6606 Max 67 6606 Figure 23 Dialogue box for selecting custom frames If you are producing custom frames for time series the Select button will display the dialogue box shown in Figure 23 Time series will be generated for each position in the list of Current values You can add new positions to the list by entering a value in the Next position m textbox then pressing the SPACEBAR Positions greater than zero are interpreted as distances from the origin positions less than or equal to zero are interpreted as distances behind the front for example 1 represents a position zs fod m Section 5 Plotting the results 1m behind the front and 0 represents the front itself The list will be sorted into ascending order as you add items to it Unwant
44. he user access to some extra parameters see below Porous Properties Porous Properties General Properties Absolute Permeability ng Depth of Porous Layer m Absolute permeability of ground in r Min 0 Max 1 Figure 10 The Porous Properties dialogue box basic version The absolute permeability and porosity fraction of unit volume that consists of pores control the rate of liquid seepage into the substrate They are entered in the textboxes labelled Absolute P ermeability m and Porosity Seepage can only occur until it reaches the depth given in the textbox Depth of Porous Layer m In typical situations the substrate below this depth is either saturated with water or is an impermeable layer If the porous layer is effectively infinite use the maximum depth 1000m 19 od a Section 4 The LSMS input data Advanced Feature If the advanced features are switched on some additional parameters are accessible from the Porous Properties dialogue box This advanced version of the dialogue box is shown in Figure 11 below Porous Properties Porous Properties Depth of Porous Layer m General Properties Absolute Permeability rr Porosity Porous Thermodynamic Properties Grain Size m Conductance s e Rel Permeability Scale Cancel Absolute permeability of around in nf Min o Max 1 Figure
45. instance if they appear in a report To save a set of graphs select the Save Graphs button on the Plot folder You will be asked to give the set a descriptive name so that you can identify it later To retrieve a saved set of graphs select the Load Graphs button A list of the graph sets saved for the current LPL file will be displayed with the name for each and the date and time on which each was saved To load a set select it in the list box and press the OK button 5 7 Copying graphs As an alternative to printing graphs it is possible to copy individual graphs to the Windows clipboard for pasting into a Windows word processing or drawing package To copy the current graph choose Copy Graph from the File menu You will then be able to paste the graph into another Windows application 5 8 Clearing graphs To discard all the graphs which have been created select the Clear Graphs button on the Plot folder You can then specify a new set of graphs using the Select Data dialogue box see Section 5 2 or reload a saved set see Section 5 6 5 9 Exporting graph data to a spreadsheet An alternative to printing a graph is to save the graph data to a text file so it can be imported into a spreadsheet such as Microsoft Excel The text file generated consists of columns of data separated by tab characters This format is widely accepted by spreadsheet packages To save the data from the graph you are currently viewing choose the Save Data b
46. ion problem The Liquid Spill Modelling System LSMS is a computer code developed by Cambridge Environmental Research Consultants Ltd CERC to predict the spreading and vaporisation of such a liquid spill LSMS has been developed for sponsors from the gas and safety industries the Gas Research Institute US BG Gaz de France and the UK Health and Safety Executive 1 2 Computer implementation LSMS has been implemented for Windows 3 1 Windows 95 and Windows NT The package consists of an interface and a model engine The interface allows the user to set up problems launch simulations and view the output produced The model engine is a separate program which carries out the simulations in the background This allows the user to continue with other tasks while the simulations proceed 1 3 Other documentation 1 The LSMS Final Report CERC report number FM140 95 1 describes the underlying mathematical model and its implementation as a computer code It discusses the capabilities of the model and gives examples from runs of the model Wi Section 2 Introduction 2 Getting started 2 1 Document structure and conventions The following conventions apply to this manual e Text which is entered into the LSMS interface is shown in Courier as follows example text e Text which is part of the LSMS interface such as a caption for an input item is shown in Arial as follows Source Radius e Keys for the user to press are shown in small ca
47. kbox The presence of bubbles in the liquid will increase the depth and therefore may have important implications for the spreading of the liquid on water or for possible overtopping of bund walls surrounding the spill Advanced Feature It is possible to modify the calculation of the void fraction bubbles in LSMS This facility is accessible by selecting the Advanced button which displays the Advanced bubble parameters dialogue box Figure 8 Advanced bubble parameters Lambda for bubbling m s Cancel rr Bubble source term constant Figure 8 The Advanced bubble parameters dialogue box The values entered here are constants in the bubble model Briefly the value entered in the textbox Lambda for bubbling m S modulates the rate at which bubbles escape through the upper surface of the pool and the value entered in the textbox Bubble source term constant modifies the amount of vapour generated at the lower boundary of the pool See Section 2 2 4 of the LSMS Final Report for more details 7 KG Section 4 The LSMS input data 4 3 The Substrate folder LSMS 1 0 TEST 01 LPL File Run Dispersion Options Help Substrate Substrate Substrate Properties Substrate Type Ground Temperature K e Homogeneous c impemescie Thermal Conductivity Kw m K 00144 Homogeneous Porous Two Layer Thermal Diffusivity nF 4 92E Wht Specific Heat Capacity kJ kg K I
48. line c LSMS LSMS and select OK From the Explorer find the file LSMS EXE in the home directory and double click it with the mouse to run it LSMS can be added to the Start menu as follows From the Explorer find the file LSMS EXE in the home directory Use the mouse to drag it onto the Start button Alternatively use the mouse to drag it onto the desktop this will create a shortcut to LSMS on your desktop From the File Manager find the file LSMS EXE in the home directory and double click it with the mouse to run it A new icon for the program can be created under Program Manager First choose New from the File menu Select Program Group and select OK Type in LsMs 1 0 as the Description and select OK Now choose New from the File menu again Select Program Item and then select OK Type in LSMS 1 0 as the Description and c LSMS LSMS EXE as the command line The first time LSMS is used on a particular machine it will ask you to confirm whether the operating system is 16 bit or 32 bit as this determines whether the slower or faster version of the model can be used Windows 3 1 3 11 and so on are 16 bit operating systems Windows 95 and Windows NT are 32 bit operating systems Wi Section 3 Basic use of LSMS 3 Basic use of LSMS 3 1 General Windows features The interface is Windows based and follows Windows conventions in its overall appearance and functionality Thi
49. lude the effects of viscosity in the simulation The liquid viscosity is calculated from information in the liquid database 2074 Wi Section 4 The LSMS input data Advanced Feature The mesh size used by LSMS is optimised so that the simulation can execute as quickly as possible while still producing accurate results Hence under normal circumstances there is no need to adjust the mesh size However if a particular case seems to be simulated with too large a grid the user can exercise some control over the mesh size used during the simulation as follows Spatial Resolution x Normal Resolution gt Fine Resolution Spatial Resolution tees Figure 19 The Spatial Resolution dialogue box Select the Spatial Resolution button from the Numerical folder This launches the Spatial Resolution dialogue box see Figure 19 This dialogue box operates similarly to the Time Resolution control explained above There is a slider which is moved along a scale the left hand end of the scale corresponds to the default resolution with a nominal value of 1 while the right hand end corresponds to fine resolution with a value of 10 In the majority of cases the default resolution is sufficient to produce accurate results Note that with an increase in resolution there is an increase in execution time 2328 Wi Section 5 Plotting the results 5 Plotting the results 5 1 Plotting overview EE LSMS 1 0 INSTK
50. m This type of source could be used to model liquid welling up from below ground The Froude number Fr is defined as Fr u g h where u is the velocity of the inflow A is the source height and g is the reduced gravity On a solid substrate g g the acceleration due to gravity but on water g g Pw p Py where p is the density of water and p is the density of the incoming fluid 222 od m Section 4 The LSMS input data symmetry Semi Angle This angle is B in Figure 5 For some configurations an adjustment to the flow rate per unit width by the factor ls defined in Figure 5 is carried out by the model Some of the dimensions of the secondary source need to be specified You cannot specify the vertical dimension Vertical Size m of a secondary spill but the source radius Source Radius m xo in Figure 5 is set by default to correspond to the perimeter of the primary spill bund You should not alter this value unless you are considering a different geometry in the secondary domain to that in the primary domain For a planar secondary domain the domain width Domain Width m bo in Figure 5 should be specified as usual i b N N K A woo We Wo bo Wo by W V n W J s P d L 1 i Sz Wo bg I Wo 2Bxp 1 wg fx Figure 5 Configurations for a secondary spill d User defined source The user defined source option allows you to design a sourc
51. mospheric flow explicitly Checked velocity recommended Measured wind speed Wind Speed m s 5 m s 0 lt x lt 100m s id Height at which wind Wind Height m 10m O0 lt x lt 50m e speed was measured Friction velocity Friction Velocity m s Calculated 0 x lt 10 m s Cn avauapre Y E IOFS cnence SPEA una height is unchecked If the wind speed has not been measured users can specify a friction velocity for the atmospheric flow 61 Ec T Section 10 Summary of input parameters Parameter Interface Default Range Type Notes BUND Whether a bund is Bund present Unchecked present Whether liquid which Model overflow Checked This option should probably be used for overtops the bund cases in which the region outside the bund should be modelled in is similar to that inside For more this simulation complicated situations secondary sources can be used see Section 4 1 1 Distance of bund Bund Radius m 50m 0 xx250m Refers to inner surface of bund wall TEDIDSQUICE This value must be greater than the source radius Thickness of bund Bund Thickness m lm 0 xx20m wall Depth of bund wall Bund Depth m 3m O0 lt x lt 100m Thermal conductivity Thermal Cond kW m K 1 44 x 10 0 lt x lt 0 01 Y of bund wall kW m K kW m K Density of bund wall Density kg m 2323 kg m 0 x 10000 i kg n Thermal diffusivity of Thermal Diffusivi
52. n may be exported from LSMS e LSMS output can be exported to version 3 00 or later of GASTAR a model developed by CERC provided both models are installed on the same computer e LSMS can create input files for HAGAR a model developed by BG e To enable users to interface with other dispersion codes LSMS can create text files containing the relevant details of the spill in a generic format These files can then be used to create any input format required by the dispersion model In exporting the results of an LSMS simulation it is assumed in all three cases that the dispersion codes treat a time dependent source by modelling the time variation as a sequence of constant inflow sources It is therefore necessary to partition the output from the LSMS run into a series of segments for the dispersion simulation Hence the user is asked to choose how this partitioning is to be carried out by means of a dialogue box see Figure 29 6 2 1 Linking to GASTAR To export LSMS output to GASTAR first of all open an LPL file for which a simulation has already been carried out Now choose Send Info To GASTAR from the Dispersion menu The first time you use this option you will be asked to find an installed copy of GASTAR Use the dialogue box Figure 28 to find the file Gaswin exe which is the main program file for GASTAR amp Please find the GASTAR interface AE File name Folders Gaswin EXE c projects NIsms tests Cancel cc A projects Ne
53. n the Options menu It is recommended that this option should not be changed once LSMS has been installed successfully 6 1 6 The advanced features of the interface The LSMS interface has been divided into basic and advanced features It is recommended that the advanced features are avoided in normal use of LSMS since these features require a more detailed understanding of the model In general the user is advised to consult the LSMS Final Report before making use of any advanced feature The advanced features can be hidden from view to prevent accidental misuse To hide the advanced features uncheck Show Advanced Options on the Options menu 6 1 7 Simulation run time graphics The Windows 95 Windows NT version of LSMS has the facility to graph the progress of the simulation as the run proceeds Users should bear in mind that this option can result in a quite significant reduction in the speed of the run depending on the graphics capabilities of the computer used To turn the graphics on check Run Time Graphics on the Options menu The options on the Graphics menu of the simulation window can then be used to control the graphics as the simulation proceeds 40 Section 6 Further features 6 2 Linking to dispersion models The results of an LSMS spill simulation can be exported to a dense gas dispersion model so that the dispersion of any evolved vapour can be modelled There are three ways in which the results of a simulatio
54. nitial Heat Flux kW n Density kg 2323 Final Heat Flux wma Slope p o Ice formation Special Properties hange Forous Properties hange Upper layer Homogeneous impermeable substrate Figure 9 The Substrate folder The Substrate folder allows you to specify the substrate on which the spill will take place There are four main substrate types 1 Homogeneous Impermeable 2 Homogeneous Porous 3 Two Layer and 4 Water We will consider each in turn 4 3 1 Homogeneous impermeable substrates This option represents a solid impermeable homogeneous substrate which contributes heat to the spill by conduction The temperature of the ground before the spill Ground Temperature K must be specified this is also the temperature of the ground far from the surface at all times during the spill The thermal properties of the substrate are coupled by the equation below thermal conductivity moira CTTUS A density x specific heat capacity Consequently you can only enter three of the four values and the fourth is then derived You can choose which value is calculated using the Options menu see Section 6 1 1 The values are entered using the textboxes Thermal Conductivity kW m K Thermal Diffusivity m s Density kg m and Specific Heat Capacity kJ kg K 18 KG Section 4 The LSMS input data Use the Slope textbox to enter the tangent of
55. ntrols the type of liquid spilled and its initial conditions It is divided into three sections 1 Liquid Type 2 Initial State and 3 Bubbles LSMS 1 0 TEST 01 LPL PIE File Run Dispersion Options Help Substrate Atmospheric Bund Numerical Plot Thermodynamics ee Liquid Type Initial State Bubbles Initial Temperature K i Set to Boiling Methane cone Advanced Ethane conc Model Bubbles X There is no status line for the curent control Figure 7 The Liquid folder 4 2 1 Liquid type The major choice on this folder is the liquid for the spill The Liquid Type drop down listbox allows you to choose a liquid from the database of predefined liquids Once a liquid has been chosen its properties can be viewed by selecting the Show Properties button This displays a dialogue box which allows you to inspect the properties of each component of the liquid The properties cannot be edited here however to edit the properties of a liquid you must use the liquid database editor see Section 6 5 4 2 2 Initial state This part of the folder allows the initial properties of the liquid to be specified For a dambreak release these represent the state of the initial volume just as it is released For a continuous source these represent the state of the liquid as it flows into the domain For a secondary release the properties of the incoming fl
56. odels 41 eee Hle eo be Lee En ERR Er ecce 41 6 2 1 Lunking to GASTAR scere eren ettet eerie ee ett FE roce Le eee eo ees eee eee gd 41 6 2 2 Creating HAGAR files ie DH Gne ee eode e Sohne eoe delia e uen a 42 6 2 3 Creating files for a generic dispersion model essere rennen 43 6 3 Running lists of problems soninn seisine e eei a i eii as reis a anea irii 44 6 3 1 Creating alist ob problems oce eet re ee etui nee Ree r ra 45 6 32 Runnmngalistof problems eene pine tede eret co eee e eee ge Le ge rni 45 644 Inquire facility iere recte tine d oce eet eet e credet eee eee eden este eee d Une RE EEEa 46 6 5 Liquid database editor iic ie eda Ue detener 47 6 5 L The lLaquid menu eee netto tp ener te Pere e E tede tee ae rt oa 48 6 5 2 Entering a liquid s properties iet ie ke et eost ree RD cL elc d eia eae nne E d Pana 48 TD IL SMS Error MesSSdages A ioi seusoscecssossnssnsescsesouetssesesteoneesees E ES oe SEES E ERES E ensis apes eie resa 49 So ThE LSMS gilt semet R 50 5 1 Program files ot ge REEL eoe deed 50 Oi2 Data IL E Lc cenite sdadea A A AE E 50 56 3 Help tiles se et prese te eve E ah tend silos Cedere Lees Order erste 51 0 4 KReSOUICES iudei eene imme tt ite o eec ute rie Had ied vectra Iob ea Raden al iR eee 51 9 Files produced for each problem wisscsssicssscsintsscsssdsasectandssbessgussoosssnvssausseteonduadeuenssseveuscasussbnetesteecsuueusuossacss 52 9 1 A list o
57. om disks 1 and 2 to the home directory the files are EXE EXE DLL EXE HLP EXE VBX EXE and INSTALL BAT 4 Run the copy of INSTALL BAT created in 3 e g type the DOS commands zs Mi Section 2 Introduction Cs CD NLSMS INSTALL 5 Once LSMS is installed and you have checked it runs see Section 2 3 2 you can save disk space by deleting EXE EXE DLL EXE HLP EXE and VBX EXE from the home directory 2 3 2 Starting LSMS In order to run LSMS the user needs to run the LSMS EXE executable This can be achieved in different ways outlined below the first two rows are alternatives for running LSMS while the third row provides a shortcut to running LSMS In these examples it is assumed that the home directory is CAL SMS Windows 3 1 Windows 95 Windows NT 3 From the Program Manager choose Run from the File menu Type in the command line C NLSMSNLSMS and select OK From the File Manager find the file LSMS EXE in the home directory and double click it with the mouse to run it A new icon for the program can be created under Program Manager First choose New from the File menu Select Program Group and select OK Type in LsmMs 1 0 as the Description and select OK Now choose New from the File menu again Select Program ltem and then select OK Type in LSMS 1 0 as the Description and c LSMS LSMS EXE as the command line Choose Run from the Start Menu Type in the command
58. oude number throughout the simulation The Froude number value is entered in the Basic Froude textbox If Surface Tension is chosen then surface tension effects are modelled in a simple way by defining a minimum height in the Surface Tension Height m textbox As the pool depth at the front approaches this value the Froude number is made to decrease to zero so that the front stops if the pool is shallow enough Comparisons with data suggest that the Froude number should be kept at around 1 2 1 4 The surface tension height would be expected to vary with roughness 0 003 m is appropriate for average roughness The value in the Turbulent Drag textbox controls turbulent drag on the pool as a whole and we model this force as a quadratic velocity term The default values are 0 01 for a solid substrates and 0 003 for spills on water It should be noted that LSMS is more sensitive to this parameter than to any other advanced parameter The value could be varied to reflect the roughness of the substrate but only with caution The value entered in the Dry Out Depth m textbox is the depth at which we deem the pool to have vanished at a given point This avoids using excessively small pool depths in the calculations when the fluid depth is in effect negligible but which might otherwise lead to problems for the calculation This value should be small but not smaller than the default value 105m Check the Include viscous shear stress checkbox to inc
59. ource type see Section 4 1 1 for details Note that this parameter must be greater than the surface tension height Simulation duration Duration s 100 s 0 lt x lt 43200 s ii Output interval Output Interval s ls 10 x lt 1000 s 7 This value Pooran he vp oial resolution in the output file 57 Ec T Section 10 Summary of input parameters Parameter Interface Default Range Type Notes LIQUID Liquid type Liquid Type listbox Methane Ifthe desired liquid is not among the options in the list box the Liquid Database editor may be used to define a new liquid see Section 6 5 How the initial Set To Boiling Checked p I EBecke dte BO temperature IS seit temperature of the its boiling point P liquid is defined Unchecked the initial temperature is explicitly set by the user Checked is recommended if the boiling point is below ambient temperature Initial temperature Initial Temperature K 111 67 K 0 lt x lt 500K 7 noraine SERE RNE d unchecked Initial composition Component 1 gt conc 1 for first jesi Specify the volume fractions of all but one Component 2 conc component MCN of the components to set the initial Component 3 conc composition of the liquid Model bubble effects Model Bubbles Checked Ts te oa Ea he Checks option is used Bubble rise velocity Lambda for bubbling m s 0 05 m s 0 x 10 m s The value of this parameter in given ci
60. ource type and geometry alters the relevance and meaning of some items on the folder Correspondingly the main discussion below is broken into four sections one for each source type and there are subdivisions within these for the different geometries where appropriate See section 4 1 2 for an explanation of the geometry items 10 od m Section 4 The LSMS input data 4 1 1 Source types and dimensions a AXISYMMETRIC Ms Xo z pat i NI T j Xx hy Mos zA TN DOE y V PLANAR 5 ho OV x 0 Xo b AXISYMMETRIC Xo Ve 2 N hy 4 i 0 ER so J PLANAR bo jt ho 5 x gt Xx p x gt Figure 4 Schematic representation of a continuous user defined source and b instantaneous dambreak source The symbols are defined in the text a Continuous inflow source This represents an inflow with a constant volume flux You must specify the volume inflow Vol Inflow m3 s and the horizontal and vertical dimensions For an axisymmetric geometry the 1 feo m Section 4 The LSMS input data horizontal dimension Source Radius m is the radial distance from the origin at which we specify the volume inflow i e the volume of liquid per unit time crossing the surface at x source radius For a planar geometry the horizontal dimension Source Length m is the location of the plane at which the volume flow rate is specified You may specify the vertical dimension Verti
61. pitals as follows SPACEBAR e The LSMS interface has been divided into basic features and advanced features It is recommended that the advanced features are avoided in normal use of LSMS since these features require a more detailed understanding of the model In general the user is advised to consult the LSMS Final Report before making use of any advanced feature It is possible to hide the advanced features see Section 6 1 6 In this manual advanced features are explained in grey boxes as shown below Advanced Feature The details of advanced features will be explained in boxes like this one 2 2 Minimum system requirements e An Intel 80386 80486 or Pentium processor e Microsoft Windows 3 1 Windows 95 or Windows NT e 10 Mbytes of hard disk space e A3 disk drive for installation e Recommended RAM 5 Mbytes under Windows 3 1 8 Mbytes under Windows 95 or NT LSMS can be used under Windows 3 1 Windows 95 or Windows NT However there are some advantages under Windows 95 and Windows NT In particular the simulations can be carried out significantly faster under these operating systems than under Windows 3 1 2 3 Installing and starting LSMS 2 3 Installation The following steps can be carried out under DOS using the Windows File Manager or using the Windows 95 Explorer 1 Keep a safe copy of your installation disks 2 Create a directory to hold LSMS e g C LSMS This is the home directory 3 Copy all the files fr
62. pool They are plotted as functions of time Total mass of liquid kg The total mass of liquid in the pool For spills on porous substrates this does not include the seeped liquid but refers only to liquid above ground Total vaporisation The rate at which liquid is being converted into vapour for the whole pool rate kg s Mass which has The total mass which has overtopped the bund up to the present time This escaped bund kg is intended as an indicator of the magnitude of the overtopping and is not the same as the total mass of liquid in the secondary region since no allowance is made for subsequent vaporisation in calculating this quantity Total mass of component kg The total mass of component in the pool For spills on porous substrates this does not include the seeped liquid but refers only to liquid above ground 5 2 3 3 Variables for averages These variables are average quantities for the entire pool i e totals averaged over the area of the pool They are plotted as a function of time Average mass of liquid kg m The average mass of liquid per unit area in the pool For spills on porous substrates this does not include the seeped liquid but refers only to liquid above ground Average vaporisation rate kg s m The average vaporisation rate per unit area for the pool Component mass fraction The average concentration of component in the
63. pool as a mass fraction For spills on porous substrates this does not include the seeped liquid but refers only to liquid above ground 33 ED a Section 5 Plotting the results 5 3 Viewing graphs LSMS 1 0 TEST 02 LPL File Run Dispersion Options Help s Type Variables riom Multiple Frames Eres E Interface interface height interface height interface height E 70 0 s M s No Frames Select Data Print Graphs Load Graphs Save Graphs Clear Graphs Graph Style Graph Axes Position m Total Height m 20 40 Select the variable to display Figure 24 The Plot folder with graphs When you have used the Select Data dialogue box to produce a set of graphs you can then view them on the Plot folder There are a number of controls at the top of the folder which affect your view of the graphs you have produced e The Display Type listbox at the top left allows you to swap between the display types for which you have produced graphs time series snapshots totals or averages e The Variables listbox to the right of the Display Type listbox allows you to choose the variable which is to be displayed Alternatively you can use the spin buttons next to it to move through the list of variables e For time series and snapshots you can use the Frame section at the top right to control which frames are displayed The listbox
64. r radiation in kW m Max 1 0 Figure 13 The Atmospheric folder The Atmospheric folder contains the data determining the effects of the atmosphere on the spill The main parameters are the solar heat flux Solar Flux kW m the roughness height and the friction velocity The solar flux is the net solar heat flux absorbed by the pool i e after the processes of reflection absorption etc have already taken place The roughness height and friction velocity are used in the evaporation model and should be representative of the flow over the pool There are several methods available for specifying these two parameters Whichever method is used the values are displayed or entered in the textboxes Roughness Height m and Friction Velocity m s There are three methods of specifying the roughness height determined by the radio buttons above the Roughness Height m text box see Figure 13 e Select Smooth to use a roughness height for aerodynamically smooth flow over the pool wind tunnels e Select Rough to use a roughness height for aerodynamically rough flow over the pool practical situations A fixed value of 2 28x10 m is used as proposed by Brighton 19857 e Select Custom to specify an explicit roughness height value yourself Brighton P W M 1985 Evaporation from a plane liquid surface into a turbulent boundary layer J Fluid Mech 159 323 345 202 KG Section 4 The LSMS input data You can choose to specify th
65. r they may ask you to make Reset all data to the default values a simple choice such as yes or no For example this message box appears when you choose the New command from the File menu It asks you to confirm that you really want to reset the input data to the default values 6 foo Am Section 3 Basic use of LSMS 3 1 12 Navigating using a keyboard Microsoft Windows environments have been developed with a mouse in mind If you do not have a mouse or prefer not to use it your Windows user guide and help files will explain how to reproduce all mouse actions using a keyboard Here is a brief guide to some useful actions Moving the cursor between input items TAB allows you to move the cursor forwards through text boxes and buttons SHIFT TAB allows you to move the cursor backwards through text boxes and buttons RETURN enters or accepts the current data page or executes the action of a highlighted button Entering data into a text box DELETE will delete the character immediately to the right of the cursor BACKSPACE will delete the character immediately to the left of the cursor CURSOR will move the cursor to the left in the current box CURSOR will move the cursor to the right in the current box HOME will move the cursor to the start of the text in the current box END will move the cursor to the end of the text in the current box SHIFT CURSOR selects text in the direction of the arrow Radio buttons lt
66. rcumstances could be established experimentally but in practice this information 1s unavailable so it is recommended that the default value is used Vapour generation factor Bubble source term constant ae 0 lt x lt 10 The value of this parameter in given circumstances could be established experimentally but in practice this information is unavailable so it is recommended that the default value is used 58 Ec T Section 10 Summary of input parameters Parameter Interface Default Range Type Notes SUBSTRATE Substrate type Substrate Type Homogeneous Choose the appropriate substrate type Impermeable Initial temperature of Ground Temperature 290 K 0 lt x lt 1000K Solid substrates ground K Thermal conductivity Thermal Conductivity 1 44 x 10 0 lt x lt 0 01 Solid substrates of bulk of substrate KW m K kW m K kW m K Thermal diffusivity of Thermal Diffusivity 4 92 x 107 m s 0 lt x lt 10 m s Solid substrates bulk of substrate m2 s Specific heat capacity Specific Heat Capacity 1 26 kJ kg K 0 lt x lt 1000 Solid substrates of bulk of substrate kJ kg K kJ kg K Density of bulk of Density kg m 2323 kg m 0 lt x lt 10000 Solid substrates substrate kg m Slope of ground Slope 0 l lt x lt l Solid substrates A positive value tangent of angle with indicates slop
67. re is an increase in execution time since the timestep is reduced by a factor of n the time resolution value hence the reason for the labels fast simulation and slow simulation at the two ends of the scale The execution time for the simulation will therefore increase by a factor of approximately n Advanced Feature You can select the Fine Control button to control the timestep more precisely than is possible with the Time Resolution control see 4 6 3 This button will launch the Advanced Numerical Parameters dialogue box Figure 17 Advanced Numerical Parameters Modify timestep during run x o Timestep Multiplier Cancel Figure 17 The Advanced Numerical Parameters dialogue box If you check the Modify timestep during run checkbox you can enter a factor in the Timestep Multiplier textbox All timesteps after that given in the Use After Step textbox will be reduced according to the specified factor This will of course increase the execution time for the simulation This facility is useful if you have a long problem case and the timestep appears to be too large at a late stage in the simulation since it allows you to use a smaller timestep only in the later stages of the simulation Using the Time Resolution control modifies the timestep from the very start of the simulation and might increase the execution time unacceptably A typical usage of this feature might proceed as follows First of all you
68. rea in kg m the mass flow rate in kg s and the vaporisation rate in kg m s Note that plots of total mass do not include liquid which has seeped into a porous substrate You can modify the range of the x axis for your graph either before or after the graphs are produced To do so before the graphs are produced select the Range button This displays a dialogue box which allows you to set the minimum and maximum values for the x axis See Section 5 4 for details of how to modify the axes after the graphs have been produced If you have chosen to produce time series or snapshots you must select one or more frames for snapshots you must give the times for which graphs are to be produced and for time series you must give the positions for which graphs are to be produced There are two methods of specifying the frames Use the Selection Method radio buttons to select one choose either Equi spaced to produce a set of equally spaced times or positions or Custom to choose specific times or positions to use Then choose the Select button to specify the frames as described in the rest of this section 30 ED Section 5 Plotting the results 5 2 1 Selecting equally spaced frames Equi spaced positions for time series Maximum position rn Interval mn Cancel Figure 22 Dialogue box for selecting equally spaced frames If you are producing equally spaced frames for time series the Select button will display t
69. rical folder provides an opportunity for the user to make some remarks about what is of particular importance or interest for the problem being set up e g a particular choice of one or more parameters a change in a parameter to examine its effect relative to an earlier run and so on It is recommended that this facility is used to help distinguish LPL files from one another If you check Prompt For Title At Save on the Options menu you will be asked to confirm the Run Title each time you save an LPL file This allows you to make sure the title is appropriate to the input data set 6 1 4 Automatic notification when simulations terminate The LSMS interface can notify the user when a single simulation finishes by displaying a dialogue box To enable this feature check Notify After Run on the Options menu The interface can also notify the user when a list of problems finishes by displaying a dialogue box To enable this feature check Notify After List on the Options menu If Notify After Run is checked the user will be notified after each simulation in the list has finished See Section 6 3 for details of how to set up and execute lists of problems 6 1 5 Choosing the 16 bit or 32 bit version LSMS can run either under Windows 3 1 a 16 bit operating system or Windows 95 or NT 32 bit operating systems The operating system is set when LSMS is installed It can be changed subsequently by checking either Use 16 bit model or Use 32 bit model o
70. run a set of LPL files sequentially using the Run List command see Section 6 3 for details Wi Section 4 The LSMS input data 4 The LSMS input data As noted in Section 3 2 the input data for a problem simulated by LSMS is specified by means of a series of folders which appear in the user interface In this section each of the six input folders and the input parameters required are described in detail 4 1 The Configuration folder LSMS 1 0 Untitled BEE File Run Dispersion Options Help Configuration Liquid Substrate Atmospheric Bund Numerical Pt Configuration Source Constant Inflow C DamBreak C Secondary C User defined Vol Inflow ri s P eS Source Froude no 0 0847 Semi Angle Choose Primary Geometry Source Dimensions Axisymmettic Planar Source Radius m e Specify vertical size X o Den Mihi Vea See Simulation Span Duration s Output Interval s P Constant inflow of liquid Figure 3 The Configuration folder The Configuration folder describes the overall characteristics of the spill There are three subsections to the folder 1 the source details 2 the geometry of the domain and 3 the timing for the simulation There are four source types namely constant inflow dam break secondary and user defined and two geometries either planar or axisymmetric The choice of s
71. s of any graphs saved for this case 52 Section 9 Files produced for each problem 9 2 The format of the spill file The spill file is a text file generated by the interface when a primary file is chosen It can be loaded into a spreadsheet such as Microsoft Excel The initial part of the file gives some details of the primary spill The main part contains the properties of the overtopped liquid as it enters the secondary domain at various times These properties are the volume flow rate m s the velocity of the overtopped fluid m s the depth of the fluid m its temperature K the concentration volume fraction of the components and the void fraction The values at a given time are separated by tab characters An example SPL file is shown below with annotations explaining the meanings of the various parts The name of the primary file Bund overtopping details for C PROJECTS LSMS TESTS 2R Y IRY 0004 LPL Primary spill details geometry x0 AXISYM 2 05 The geometry and source radius for the primary spill Time s Vol flux m3 s Velocity m s Height m Temp K Methane Void fraction 0 0 0 0 0 0 0 6008021 9613308 5816565 8 422897E 02 106 2769 9023081 0 6495984 1 617334 6219032 119146 106 2648 9026707 0 699274 1 477859 4718661 1121937 106 2422 9021116 0 7505329 1 164299 3583193 106 2842 9023941 0 7995006 1 060452 3337446 0899236 106 3137 9031301 0 8506654 1 066397 3348505 9 025934E
72. s section outlines some general issues for the use of the interface Please see your Windows manuals or help files for further information LSMS 1 0 INSTKWI2 LPL Bun Dispersion Options Help MC uuo Substrate Atmospheric Bund Numerical Piot Open Save Save As Configuration Source Constant Inflow Dam Break Secondary User defined Print Copy Graph Edit List Ww m s Width mo View Edit Source Ghoose Primary Geometry Source Dimensions Axisymmetric Planar Source Radius m Specify vertical size x Domain Width m Vertical Size m 5 J Simulation Span Duration s Dutput Interval s jJ Horizontal extent of source in m Max 100 Figure 1 The LSMS interface with the File menu open 3 1 4 The menu bar File Run Dispersion Options Help The main LSMS window has a menu bar at the top below the title bar containing a number of menus Each menu contains a list of commands which are actions you can carry out in Windows To choose a menu name or a command you click it once with the left mouse button Clicking a command carries out an action Menu items with an arrow to the right such as Print in Figure 1 will produce sub menus when selected These sub menus contain further lists of commands KG a Section 3 Basic use of LSMS 3 1 2 The help bar Volume inflow at source in m s Min
73. s substrates this does not include any seeped liquid but applies only to liquid above ground Velocity m s The velocity of the liquid in the pool Mass flow rate kg s The mass flow rate of the liquid in the pool Component The concentration volume fraction of component For spills on porous concentration substrates this refers only to the liquid above ground Component vapour concentration The concentration of component in the vapour as a volume fraction or equivalently a mole fraction since we treat the vapour as an ideal gas Temperature K The temperature of the liquid For spills on porous substrates this refers only to the liquid above ground Vaporisation rate mm s The rate at which liquid is being converted into vapour surface regression rate Vaporisation rate kg s m2 The rate at which liquid is being converted into vapour in mass based units Position m The position for which values are being plotted time series plots only This is useful only when a position has been given relative to the front and therefore varies with time Void fraction The fraction of the pool depth which is occupied by bubbles For spills on porous substrates this refers only to the liquid above ground 2 80 E m Section 5 Plotting the results 5 2 3 2 Variables for totals These variables are total quantities summed over the entire
74. s the files in the current list e To add a new file to the list first find it using the controls at the left side the list box at the top left allows you to change to another drive and the listbox at the centre left allows you to find the correct directory Then highlight the file in the listbox at the bottom left and select the Add To List button or double click the file with the mouse e Files can be removed from the Current list by double clicking them with the mouse e Use the Clear List button to remove all files from the current list and begin again from scratch e You can open an existing list file by selecting the Open List File button and selecting the file in the resulting dialogue box e You must save a list to a file before you can use it to carry out a batch of simulations To do this select the Save List File As button You will then be prompted to provide a file name 6 3 2 Running a list of problems Once you have created and saved a list of problems they can be executed by using the List command from the Run menu You will be asked to choose a list file then the LPL files listed in it will be executed in sequence 45 Cod Section 6 Further features 6 4 Inquire facility LSMS allows the user to obtain the numerical values of the pool properties at a specified time and position during the simulation This is done by selecting the Inquire button from the Plot folder which displays the Examine Output dialogue bo
75. should find that a particularly long simulation is failing to reach the end time and the log file contains a message like the one in Figure 16 you should increase this value LSMS Liquid Spill Modelling System Double Precision 32 bit Edition MER Edd pO roar Most of the log file has been omitted Se 000 9 60097 192E 00 1000 192 6 797 192E 02 2000001 250 89 7 Program terminated because of large number of timesteps 2000001 taken limit is 2000000 Run completed in 89 72 seconds real time Figure 16 A log file for a simulation which took too many timesteps 225 fo A Section 4 The LSMS input data 4 6 3 Time resolution The timestep used by LSMS is optimised so that the simulation can execute as quickly as possible while still producing accurate results Hence under normal circumstances there is no need to adjust the timestep However if a particular case seems to be simulated with too large a timestep the user can exercise some control over the timestep size used during the simulation by means of the Time Resolution feature This control consists of a slider which is moved along a scale the left hand end of the scale corresponds to coarse resolution with a nominal value of 0 5 while the right hand end corresponds to fine resolution with a value of 6 In the majority of cases the default resolution of 1 is sufficient to produce accurate results Note that with an increase in resolution the
76. sion menu The dialogue box shown in Figure 29 will appear Specify the partitioning of the LSMS run into segments as explained in Section 6 2 1 A file will be created with the same filestem as the LPL file but with the extension TXT The data in the file is in columns separated by tab characters see Figure 31 It consists of average values at various times for the vaporisation rate kg s the width of the pool m the temperature of the vapour K its density kg m and the concentrations mass fractions of the components of the vapour 2435 fod f m Section 6 Further features Time s Vap rate kg s Width m Temp K Density kg m Conc Methane 2 54 85321 24 54736 111 8662 1 77169 1 000 6 120 3766 30 98344 111 8198 1 863088 1 000 10 177 4817 37 21472 111 791 1 794889 1 000 14 217 3003 42 53863 111 7713 1 782505 1 000 18 253 4168 47 277015 111 7592 1 772454 1 000 22 282 0639 51 5599 111 7496 1 768677 1 000 26 307 3297 55 51102 111 742 1 766356 1 000 30 331 0158 59 09095 111 7363 1 759716 1 000 34 350 5164 62 44209 111 7313 1 760468 1 000 38 369 468 65 59709 111 7272 1 759956 1 000 42 387 6699 68 57581 111 7239 1 757404 1 000 46 404 2445 71 42577 111 7209 1 757914 1 000 50 421 84 74 13533 111 7186 1 756503 1 000 54 436 6907 76 74989 111 7162 1 755139 1 000 58 451 6053 79 28918 111 7142 1 756896 1 000 62 467 1133 81 72985 111 7125 1 756552 1 000 66 481 2026 84 07809 111 7108 1 755604 1 000 70 495 3314 86 3613 111 7094 1
77. taining the current selection however when you select the box the list of available choices appears If there are more items than can fit in the box scroll bars are provided LNG with nitrogen LNG with propane or by pressing the SPACEBAR provided the checkbox is selected If it is selected it will have a dashed box around it as shown here 3 1 7 Radio buttons Radio buttons represent a group of mutually exclusive options i e you can select only one option at a time and if you select a ej NEAN Pate new option the previous one becomes unselected The C Two fum selected option contains a black dot Names of options which C Water cannot be selected appear dimmed In this example the substrate type has been selected as Homogeneous Impermeable Substrate Type Homogeneous Impermeable 55e KG am Section 3 Basic use of LSMS 3 1 8 Command buttons You choose a command button to initiate an action Unavailable buttons Show Properties appear dimmed The currently selected button has a border that appears darker than that of other buttons and you can initiate the action associated with the selected button by pressing ENTER You can initiate the action associated with any button selected or not by clicking it with the mouse 3 1 9 Spin buttons You move forwards down through the list by clicking the down arrow with the mouse Spin buttons are used to cycle through an ordered list You move forwar
78. the file filename The LPL file could not be opened The most common cause of this is an attempt to run an LPL file which does not exist Unable to open the user defined source The SRC file containing details of the user defined source could not file filename be opened The file may have been accidentally deleted or the LPL file may have been copied to another directory without the corresponding SRC file Use the interface to examine the details of the user defined source Unable to read the spill file for The SPL file containing details of the bund overtopping for the spill filename filename could not be read Try opening the LPL file which you were attempting to run and reselecting the primary spill Error on opening output file One or more of the output files could not be created This may be caused by an old output file having a read only status Try saving the LPL file under a new name and running the simulation again Truncation error giving small step Truncation errors in the numerical solution are forcing the timestep to become very small This may increase the execution time for the simulation significantly Warning too many bisections for The liquid temperature could not be determined accurately This temperature in FindTemp warning is unlikely in normal usage of LSMS Warning no solution for Zbar after n The vaporisation rate from the pool could not be determined This iterations warning is unlikely in normal usage of LSMS
79. the left of the option name if they are turned on To switch the state of these options between on and off select the menu option in the usual way 6 1 1 Thermal diffusivity options In several sections of the interface LSMS requires the specification of the thermal properties of a material specifically thermal conductivity k density p specific heat capacity C and thermal diffusivity x These properties are linked by the relation x k p Cp Consequently only three of the properties need to be entered and the fourth is calculated You can control which value is calculated by selecting Therma Diffusivity from the Options menu This displays the Options for entering linked thermal properties dialogue box see Figure 27 Simply select the value which you want to be calculated from the Chosen method radio buttons Chosen method Calculate density Options for entering linked thermal properties PERSE ieee ces ema TM Cancel C Calculate thermal conductivity C Calculate specific heat capacity Figure 27 The dialogue box for controlling the linked thermal properties 6 1 2 Including problem summaries with printouts To include a printed summary of the problem input data automatically with each printed set of graphs check Print Summary W ith Graphs on the Options menu 39 fod 2m Section 6 Further features 6 1 3 Prompting for run titles at each save The Run Title on the Nume
80. tion is complete the Plot folder can be used to produce graphs of the simulation results which can be printed or saved for easy retrieval later The use of the Plot folder is explained in detail in Section 5 The exception is user defined source data which is contained in files with the extension SRC See Section 4 1 1 8 KG Section 4 The LSMS input data 3 2 1 The File menu e New resets your input data back to the default values e Open reopens an LPL file which has been saved earlier Save e Save saves the current set of input data to an LPL file which may already Save As exist Print e Save As saves the current set of input data to a new LPL file Copy Graph E dit List e Print has two sub options Summary prints a summary of the current set of input data Graphs prints the current graphs from the Plot folder See Section 5 for details on creating and printing graphs Exit 3 2 2 The Run menu Dispersion Once a case has been created and stored in an LPL file you can run it in a Run File simulation This is done using the Run menu pictured at left Run List e Torun asingle simulation choose the Run File command A dialogue box will appear asking you to choose which LPL file to run If you already have an LPL file open this will appear as the default otherwise you must find the LPL file you want to use Press RETURN or click the OK button to begin the simulation e tis also possible to
81. twork CX Isms tests a 2 Read only List files of type Drives GASTAR Interface amp J c mark s disk di Figure 28 Dialogue box for locating GASTAR installation The GASTAR interface will then be launched Next you will be asked if you want to use the pool uptake model in GASTAR This module of GASTAR models the formation of a vapour cloud above the liquid pool and produces a time varying source for the main GASTAR model Users are referred to the GASTAR documentation for more details sd ED a Section 6 Further features The dialogue box shown in Figure 29 will then be displayed so that the LSMS run can be partitioned into segments for the GASTAR simulation see above The duration of the LSMS run is shown at the left of the dialogue box The user enters the start and end times and the number of segments into which the LSMS results are divided for interpretation by GASTAR using the text boxes Start time s Stop time s and Segments Choose the time domain for the source of the dispersion simulation x Durations of the individual LSMS runs Start time fs op 0 0 100 0 C PROJECTS LSMS REPORTS NEWP Stop time si Cancel Figure 29 Dispersion time domain dialogue box On selecting OK the LSMS interface will then calculate average values of the vaporisation pool size etc for use in each segment of the GASTAR simulation Finally the GASTAR interface will
82. ty 4 92 x 10 m s 0 lt x x 10 m s x bund wall m s 62 T Section 10 Summary of input parameters Parameter Interface Default Range Type Notes NUMERICAL Run title Run Title Default run T This space should be used to provide a brief description of the problem Maximum number of Maximum No Of 2 000 000 10 lt x lt This number may need to be increased for timesteps for a Timesteps 10 000 000 very long runs see Section 4 6 2 simulation Maximum number of Maximum No of Grid 200 10 lt x lt 800 This number may need to be increased to grid points used for a Points increase the smoothness of the solution simulation Time resolution Time Resolution 1 0 5 lt x lt 6 This number may need to be increased to increase the smoothness of the solution It can also be decreased to reduce the runtime of the simulation but at the user s own risk Spatial resolution Spatial Resolution 1 1 lt x lt 10 This number may need to be increased to increase the smoothness of the solution Front treatment Front treatment Surface Tension Constant Froude Number the Froude number at the front remains constant throughout the simulation Surface Tension surface tension effects are modelled Basic Froude number for Basic Froude 1 4 0 xx10 Comparisons with data suggest that this Froude the front number should be in the range 1 2
83. uid above ground level The Vaporisation Rate mm s textbox shows the rate at which vapour is escaping from the pool at the specified point in terms of the depth of liquid being lost per second For spills on water the depth of the lower interface below sea level is shown in the textbox 46 ED a Section 6 Further features Depth Below Water m For spills on a porous substrate the seepage depth is shown in the textbox Saturation Depth m The Total Mass kg textbox shows the total mass of liquid For spills on a porous substrate this does not include liquid which has seeped into the substrate The Mass of Component kg textbox shows the total mass of the first component in the liquid For spills on a porous substrate this does not include liquid which has seeped into the substrate The Total Vaporisation kg s textbox shows the total mass of vapour which is escaping from the pool per second The Average Concentration textbox shows the mass fraction of the first component in the entire pool The Average Mass kg m textbox shows the average mass of liquid per square metre in the pool For spills on a porous substrate this does not include liquid which has seeped into the substrate The Front Position m textbox shows the position of the liquid above ground and furthermost from the source The Area m and Volume m textboxes show respectively the surface area and volume of the entire pool at the time given 6 5 Liquid d
84. uid are determined by the primary spill and this section is disabled For 16 od a Section 4 The LSMS input data a user defined source the initial state of the incoming liquid may vary throughout the spill This variation is controlled by the user defined source dialogue box which is accessed from the Configuration folder and consequently the Initial State section is disabled for such sources The temperature of the liquid Initial Temperature K can be specified explicitly or the liquid can be set to its boiling temperature which is dependent on concentration for a multicomponent liquid by checking the Set to Boiling checkbox It is recommended that spills of cryogenic liquids are modelled using this feature to set the initial temperature to the boiling temperature If the liquid is multicomponent you must specify the initial composition This is done by giving the initial concentration volume fraction for all the components but one the missing concentration is then set automatically so that the sum of all the concentrations is 1 For example Figure 7 shows the liquid folder being used to define the initial state for a spill of LNG which is made up of methane and ethane The initial concentration of methane has been entered as 0 92 the corresponding ethane concentration has been set to 0 08 by the interface 4 2 3 Bubbles You can choose to include the effects of bubbles in the simulation by checking the Model Bubbles chec
85. utton from the Plot folder You will be asked to give a filename for the text file The data for the current graph will be saved into this file To load this file into Microsoft Excel version 5 0 choose the Open command from the File menu and select the file you have just created Excel will start the file import Wizard where you can specify how the file is to be interpreted Excel should be able to detect the file type and fill in the Wizard appropriately but it is worth checking these settings to make sure this process has succeeded On the first screen make sure that the Original Data Type is Delimited Move to the second screen and make sure that only the checkbox marked Tab is checked in the Delimiters section On the third screen simply click Finish The graph data should appear in a new worksheet 38 Wi Section 6 Further features 6 1 Options SE Help Thermal Diffusivity Print Summary With Graphs Prompt For Title amp t Save Notify After Run v Notify After List Use 16 bit model v Use 32 bit model v Show Advanced Options Run Time Graphics 6 Further features It is possible to customise the behaviour of the LSMS interface and simulation engine by using the commands available on the Options menu pictured at left The individual options are explained in detail in the sections below Those options which are either on or off such as Show Advanced Options have a tick to
86. x Figure 33 Examine Output B Location Position m Time s b0 01676 Liquid Properties Pool Depth m Total Mass kg 582669 8 Velocity m s Mass of Methane kg 914027 2 Concentration Total Vaporisation kg s 2267 836 Temperature K Average Concentration 882193 Vaporisation Rate mm s Average Mass kg m 23 19372 Saturation Depth m Front Position m 89 41182 Density kg m ean 25115 38 Volume nP 1334 313 ee Time of interest s Min 0 Max 50 01676 Figure 33 The Examine Output dialogue box To obtain the properties of the pool at a given place and time enter the position distance from the origin and the time of interest in the textboxes Position m and Time s then select the Update button Your specified time will be replaced with the nearest time for which output was stored The left side of the dialogue box will be filled with the properties of the pool at the position and time specified and the right side with total and average properties for the whole pool at that time The interpretation of the output may need a little clarification The Pool Depth m textbox shows the total depth of the pool The Velocity m textbox displays the velocity of the liquid away from the source The Concentration textbox shows the volume fraction of the first component in the liquid at the position and time given The Temperature K textbox shows the temperature of the fl
87. x lt 10 s Porous substrates It is recommended that the default value is used Depth of upper layer Layer Depth m 0 1m O lt x lt lm Two layer substrates Thermal conductivity Thermal Conductivity 1 44 x 10 0 lt x lt 0 01 Two layer substrates of upper layer kW m K kW m K kW m K Thermal diffusivity of Thermal Diffusivity 1 427 x 10 0 x 10 m s Two layer substrates upper layer m s m s Specific heat capacity Specific Heat Capacity 1 26 kKJ kg K 0 lt x lt 1000 Two layer substrates of upper layer kJ kg K kJ kg K Density of upper Layer Density kg m 801 kg m 0 lt x lt 10000 Two layer substrates layer kg m 60 Ec m Section 10 Summary of input parameters Parameter Interface Default Range Type Notes ATMOSPHERIC Solar heat flux Solar Flux kW m 0 5 kW m 0 lt x lt 10kW m2 This parameter is generally only significant for spills of volatile liquids Roughness height Roughness Height Rough ons ADU for pun cunts caleulatiom method radio buttons Rough value for practical situations recommended Custom user specified value Roughness height Roughness Height m Calculated O0 lt x lt 10m CHES GURU AION GN S EE text box Whether to use Use reference speed Checked Date dont you wend i measured wind speed and height specify the friction velocity for the P EE dion at
88. y is bo c Secondary source This type of source models the evolution of fluid spilled from a bund The simulation in which the overtopping occurred is known as the primary case You must choose an LPL file for the primary case by using the Choose Primary button which displays a dialogue box similar to the one displayed by the Open command on the File menu The configuration of the secondary domain must be defined see Figure 5 for diagrams of possible configurations You must specify a width for the secondary domain Width m This width is wo in Figure 5 and is the length of the part of the perimeter of the primary spill bund over which liquid spills into the secondary domain This value should not exceed the total length of the perimeter of the bund wall in the primary spill Note that it is necessary to take into account the finite thickness of the bund wall in calculating the width i e perimeter refers to the outer radius of the bund wall Also when the ground slopes in the primary spill it is necessary to allow for this when calculating the perimeter of the primary source and therefore the value of the width i e if Ois the slope angle and is the bund height then the effective bund radius is increased from ry to ry cos 4 hy sinO If the secondary domain is an axisymmetric sector you must specify the semi angle at the axis of The underlying assumption for the latter is that the inflowing liquid has no horizontal momentu
89. ype Source radio buttons Continuous Choose the appropriate source type for the case This choice affects several other parameters on this folder Volume inflow Vol Inflow m3 s 10 m3 s 0 lt x 1000 m3 s T Continuous releases Secondary width Width m Calculated 0 lt x lt 2000 m Secondary sources This parameter should be varied if the geometry of the secondary region is different to that of the primary region See Section 4 1 1 Secondary sector Semi Angle Calculated 0 lt x lt 180 Secondary sources This parameter semi angle should be varied if the geometry of the secondary region is different to that of the primary region See Section 4 1 1 Geometry Geometry Axisymmetric k Choose the appropriate geometry either radio buttons axisymmetric spreading equally in all directions or spreading into a sector or planar e g a spill in a channel This choice affects several other parameters on this folder Transverse width of Domain Width m lm O0 lt x lt 100m PONAT PUNS the flow domain Streamwise Source Radius m or 6m 0 xx100m a Eene pretan on Ob tiig depends onthe source type see Section 4 1 1 for details 56 Ec T Section 10 Summary of input parameters Parameter Interface Default Range Type Notes CONFIGURATION cont Vertical dimension Vertical Size m 1m 0 xx100m x The interpretation of this depends on the for source s

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