HyperFEA Analysis Problem

[Toakey]

Hi, I have been trying to get HyperFEA working in conjunction with MSC Nastran, but when i try to run more than one iteration in HyperFEA I get the following error (using the HyperFEA tutorial project as an example):
Problem Analysing FEM "C:\Hypersizer Data\Projects\_HyperFEA\FEA\Ap1_i02.dat"
FEA Forces needed by Hypersizer not found.
I have changed the nastran_submit batch file to target the mdnastranw.exe, however I am running Nastran via a VPN. Would this have any effect on HyperFEA calling on Nastran?
Any help would be greatly appreciated,
Thanks

[Toakey]

Well, I shall answer my own question, turns out I should have been targetting the mdnastran.exe, no w required, didnt see that in the HyperFEA manual for a while. I suppose a mod can delete this thread now, since the point is moot =]
Thanks

[Ryan]

Yes, the "w" Nastran executables will attempt to open up a Windows file dialog box which is not compatible with "batch" mode.

As another tip, you can test out the nastran_submit.bat file from the command line. This way you verify that the batch file is set up correctly before launching HyperFEA.

Code: [Select]

C:\Temp>cd C:\Program Files\HyperSizer\HyperFEA

C:\Program Files\HyperSizer\HyperFEA>nastran_submit.bat "C:\HyperSizer Data\Projects\Collier\_Training UM\RLV\FEA\rlv.dat"

BatchFile: C:\Program Files\HyperSizer\HyperFEA\nastran_submit.bat
FEM Drive    : C:
FEM Path     : C:\HyperSizer Data\Projects\Collier\_Training UM\RLV\FEA\
FEM FileBase : RLV
FEM Extension: .dat
Full Filename: RLV.dat
NASTRAN      : "C:\MSC.Software\MSC_Nastran\20101\bin\Nastran.exe"
MSC.Nastran V2010.1 (Intel Windows XP 5.1 (Build 2600)) Fri Sep 09 09:22:22 2011

*** SYSTEM INFORMATION MESSAGE (pgm: nastran, fn: estimate_job_requirements)
    Starting ESTIMATE, please wait...

*** USER INFORMATION MESSAGE (pgm: nastran, fn: estimate_job_requirements)
    Estimated DOF=4895
    Estimated memory=128.0MB
    Estimated disk=23.6MB

    Note: ESTIMATE had some difficulty analyzing this job.
MSC.Nastran beginning job rlv.
MSC.Nastran started  Fri Sep  9 09:22:23 EDT 2011
MSC.Nastran finished Fri Sep  9 09:22:34 EDT 2011
MSC.Nastran job rlv completed.

C:\HyperSizer Data\Projects\Collier\_Training UM\RLV\FEA>


[Toakey]

Hi thanks for the prompt reply, so I have Nastran and HyperFEA adequetly iterating between each other. However, when I try to implement one of my own models for analysis I am still getting the same error that Hypersizer cannot analyse the next i02.dat file, FEA forces not found.
Is there a particular card or command I need to put into my Nastran model to ensure that the proper force outputs needed by Hypersizer are created.
Thanks again

[James]

In v6.1.69 and before, HyperSizer will read the FEA element forces from the .f06 file (.ELS for NEi Nastran). You will need to include the following line in the case control so Nastran prints the FEA forces to the .f06 file.

FORCE(PRINT) = ALL

See related help topic: http://hypersizer.com/help/index_CSH.php#FEM-Nastran/nas-07-load_sets.php

If this command is already in your .bdf, then Nastran may have exited before printing loads to the .f06 file. Open the _i02.f06 file and search "fatal". Is there an error? Is it a singularity in your FEM? Is there duplicate material cards?

Sometimes, in previous versions ( < v6.1.85), HyperSizer will print duplicate material cards to the .pm1 file which will cause errors in Nastran. See related forum topic: http://hypersizer.com/forum/index.php/topic,355.msg856.html#msg856

FYI...This issue has been fixed in v6.1.85. Contact us for an update.

[James]

Also, make sure that the nastran_submit.bat file has "" around the very last word in the file. The last line should appear as...

%NASTRANEXE% "%FEMFILE%"

[Toakey]

Hi James, I had a look through the Nastran file and the .f06 files wasnt printing out the forces so after I added the FORCE(PRINT) = ALL command it seemed to correct my issue. It probably would have saved me a bit of time if I read through all the forum threads properly, I seemed to have missed that one. Thanks for all your help.