文本文稿msc.patran courses课程setup

1、SECTION 12ANALYSIS SETUPANALYSIS SETUPThe Analysis forms are automatically set to correspond to the user-selected analysis code, e.g. MSC.Nastran (*).Analysis parameters are specified using these forms.Optionally, can submit and monitor the status of the analysis job(s) across the network.Access the

2、 solver results fileFor Nastran, this form can also be used to read an existing bulk data file into the Patran database; Nastran files can also be read using File/Import.*SOME ANALYSIS FORMSThese forms show, in brief, some of the possible choices:The comments below are specific to Nastran. However,

3、there are similar features for other solvers, e.g. Marc.The analysis model may be prepared for:Entire Model the entire model in the Patran database, regardless of what is posted to the viewport, is submittedSelected Group the model in only the specified group, e.g. group_1, is submittedAfter selecti

4、ng the desired group click the Cancel buttonSETTING UP THE ANALYSISSETTING UP THE ANALYSIS (Cont.)The analysis model may be prepared for (continued):Existing deck direct Patran to submit an existing Nastran deck (file) for an analysis. Simply select the analysis Job Name. Can also edit the analysis

5、deck from within Patran.Restart set-up a restart analysis deck (file) using an existing analysis Job Name and creating a new restart Job Name. This is only supported for SOL 101, 103, and 106.Interactive allows the set-up of a modal frequency response analysis using modes from a previously run norma

6、l modes analysis. Loads and output requests may be defined, a fast restart performed, and results viewed. Can be used only if the model was created in Patran.SETTING UP THE ANALYSIS (Cont.)Job NameImportant tool in the Analysis formServes several purposesPrefix name of analysis deck (file), jobname.

7、bdf, and resulting analysis files generated by Nastran, i.e. jobname.f04, jobname.f06.Name stores all the settings of the Analysis form used to generate the job, going from Patran to NastranCan create a Job Description that “tags” along with Job Name in the Patran database for future referenceServes

8、 as a cross-reference link when importing results between database stored subcase / load case names and result file subcase / load case namesBe careful when deleting job names. All files generated using that job name (in the database directory) will also optionally be deleted.Select Translation Para

9、meters to specify:TolerancesUsed for numerical manipulation during export translation“Division” tolerance used to prevent divide by zero errors; default is 1.0e-8.“Numerical” tolerance used in determining if two real values are equal; default is 1.0e-4.“Writing” tolerance used to determine when a fi

10、eld entry is approximately zero; default is 1.0e-21.Bulk Data FormatSorted Bulk Data - Option to write out alphabetically sorted entriesCard Format - determines whether entries are written in small or large format (or a mixture)Write Stored Precision writes double precision data if available SETTING

11、 UP THE ANALYSIS (Cont.)Select Translation Parameters to specify (continued):Precision Control Options - Specifies precision to use when writing various values. For instance if this value is specified as 2 the number 1.3398 will be written out as 1.34. SETTING UP THE ANALYSIS (Cont.)Select Translati

12、on Parameters to specify (continued):Nastran VersionExport the model using that version of Nastran, i.e. version 2005, 2001, 70.7For a “Full Run”, analysis causes the submission of the job to that version of the Nastran executableWrite Properties on Element EntriesBulk data element entry with proper

13、ties on it, e.g. CELAS2Write Global Ply IDsConvert CBARs to CBEAMsSETTING UP THE ANALYSIS (Cont.)SETTING UP THE ANALYSIS (Cont.)Select Solution Type to specify the type of solver analysis and apply appropriate parametersSETTING UP THE ANALYSIS (Cont.)Select Solution Type to specify the type of solve

14、r analysis and apply appropriate parametersSolution ParametersDatabase RunSwitching off will invoke old unstructured solution sequences, e.g. SOL1Automatic Constraints - sets AUTOSPCOther check boxes invoke additional solution sequencesPlate Rz Stiffness FactorSpecifies K6ROTSETTING UP THE ANALYSIS

15、(Cont.)Select Solution Type to specify the type of solver analysis and apply appropriate parametersResults Output FormatSpecify type of results output desired (PARAM,POST)XDB or OP2, with or without f06 output, & with or without Punch fileResults written to MASTER or MASTER/DBALL XDB buffer size, e.

16、g. 1024Direct text input (DTI) allows the insertion into the Nastran input file of any extra data that may be needed to define the runSETTING UP THE ANALYSIS (Cont.)SETTING UP THE ANALYSIS (Cont.)Direct text input (continued)Commands/entries may be entered in the various sections of the input file,

17、i.e. Executive, Case Control, and Bulk Data SectionsNastran System Cell commands may also be defined via DTI“Reject” cards from a Nastran Deck (file) import may be exported to a newly created deckSETTING UP THE ANALYSIS (Cont.)Create subcases under SubcasesIn Patran a Subcase is the combination of a

18、 Load Case, Subcase Parameters, Output Requests, DTI, Superelement definitions, and Selected Explicit MPCsSETTING UP THE ANALYSIS (Cont.)Subcase creation:Subcases are automatically generated for each Load Case. Can also manually create new ones.For specified new Subcase Name, select an existing Load

19、 Case under Available Load Cases.Specify Subcase Parameters, Output Requests, DTI, and Explicit MPCs.Click Apply.SETTING UP THE ANALYSIS (Cont.)Select the subcases already defined using Subcase SelectThe run-ready file can be submitted directly to Nastran from within Patran, or the file can be submi

20、tted outside PatranSETTING UP THE ANALYSIS (Cont.)Subcase Output RequestsTwo ways to specify Output Requests:1: Output for single SubcaseSETTING UP THE ANALYSIS (Cont.)Output Requests, one SubcaseThere are two types of forms: Basic and AdvancedBasicBasic simply allows for the selection of a result t

21、ype, and the acceptance of the defaults of the output requestAdvancedAdvanced allows for more optionsSelect a result type for the chosen SOL type, and choose the appropriate options for the output request, including whether or not to output results to the .f06 fileAny group that is created can be us

22、ed as an Nastran SET. It is not necessary to output results for all entities.Click OK for the form, and Apply for the Subcases form to save the selectionsSETTING UP THE ANALYSIS (Cont.)Subcase Output Requests (continued)Two ways to specify Output Requests2: Output for multiple SubcasesSETTING UP THE

23、 ANALYSIS (Cont.)Output Requests, multiple SubcasesSubcases/Action: Global DataSelect Subcases that are to have the same output requests, and click on Output Requests buttonSelect column or individual cells for which output is desiredSelect SETs where appropriate, along with Output Request optionsCl

24、ick OK in the middle of the form to insert Output Request Command to cell(s)When finished with Spreadsheet, click OK on the panel, and click Apply in Subcases/Action: Global Data formRESULTS TRANSLATION INTO PATRANResults can be accessed by Attach XDB, Read Output2, Attach MASTER, Attach T16/T19, or

25、 Attach d3plotIn general, either the results or model, or both can be accessedResult Entities: stresses, displacementsModel Data: nodes, elementsBoth: both model and resultsRESULTS TRANSLATION INTO PATRAN (Cont.)Patran does not read the results .XDB data file into the database. It attaches the .XDB

26、file which results in the storing of only metadata (result case names and the .XDB file location) in the Patran database. After attaching the file, the .XDB file must be kept in the file system. MASTER and T16/T19 do the same thing since they use a similar DRA (direct results access) method to attac

27、h the files.OP2 import physically imports and stores the results in the Patran database. The OP2 file is not needed after import.XDB attached results can be accessed more quickly from Patran than OP2 imported results.RESULTS TRANSLATION INTO PATRAN (Cont.)All Options have 3 choices for what to impor

28、t, except for T16/T19 which has only results or modelResults Entities - attach/import only the results portion of the fileModel Data - import only enough of the FE model so the results can be displayed on the FE entitiesBoth - attach/import results and skeleton portion of the FE modelModel Data (onl

29、y model) characteristicsXDB - imports grids, element topology, coordinate frames, and superelement group informationOP2 and T16/T19 - imports grids, element topology, and coordinate framesMASTER - reuses the .bdf import capabilityRESULTS TRANSLATION INTO PATRAN (Cont.)If an XDB file gets changed (co

30、ntents or time/date stamp) or gets moved, and it is attached to an Patran database, it will be necessary to delete the attachment and re-attach the fileAttach XDB requires that the file be “seen” on the system. It can be either local or NFS mounted to the machineThere is no limit to the number of XD

31、B files that can be attached to an Patran database, or to the number of users attaching to a single XDB fileA Control File called .jbr is created by the OP2 import or the T16/T19 attachment. The File describes what translator and options were used, along with the file imported.Failure indices can be

32、 imported into Patran via the OP2 file, but not currently the XDB file.OP2 results file import is no longer being enhanced in Patran. Only bug fixes and general maintenance is being done.RESULTS TRANSLATION INTO PATRAN (Cont.)Translation parameters are used to direct the importing processTolerancesA

33、dditional results to be importedRESULTS TRANSLATION INTO PATRAN (Cont.)Translation ParametersFrequently ignored by many Patran users. Not a good thing!Direct the import translator on the additional types of results quantities to import, i.e. rotational nodal results, stress/strain invariants, etc.Su

34、ggest turning switches on for Rotational Nodal Results and Stress/Strain InvariantsT16/T19 Attachments do not provide these options but provide a Translation Parameters buttonEven though Element Results Positions is defaulted to Nodal, ALWAYS set to BothEnsures that Patran is importing Nastran resul

35、ts for all result positions (Centroidal/Nodal)Reduces the opportunity for Patran to be used to manipulate the Nastran results dataREADING NASTRAN BULK DATA FILEExisting Nastran bulk data files can be read into Patran to verify and update models that were not created inside PatranThe Nastran bulk data file reader is used to translate the model into PatranAny statement not recognized will be optionally displayed in a window by area, file management section, executive section, case control section, or bulk data section