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Here is my problem, i received a body-in-white in the bdf format which, by reading the file, seems to have been created through Patran 2013 and i need to make some changes to the body-in-white. I use LMS Virtual Lab in order to make my modifications but unfortunately with Virtual Lab i can only import the bdf file and then after modifications i need to export the work into a new bdf file. One remarkable difference is the size of the bdf file shortening from 128MB to 92MB.

My next step is to compute the normal modal analysis through MD Nastran which works fine with the original bdf file giving me an OP2 result file. However with the modified bdf file it runs, gives an exit(0) (which means no abnormal exit) as does the original file and then when i try to look at the resulting OP2 file (in Nastran NX) it tells me it can't find any results (whereas in the original it does).

Any thoughts ?

Guillaume
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1 Answers1

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Maybe you already found the answer but I would do the following:

First step would be to check f06 for Fatal Errors. If no errors found, you can check if Eigenvalues are listet in f06. If no clue by checking f06, I would check what LMS is doing with the model:

1.) input original file in LMS and output it as BDF -> check if output-file contains same entities as input-file (number of grids,number of rbe2/3, number of quads,trias,hex, number of forces,spc)

2.) if 1.) shows you that input and output are the same, this means that LMS output-settings are ok

3.) if 1.) shows that there are some small differences, but size of the file is the same it means that some LMS settings are not suitable for your output -> check LMS output Settings -> start modal analysis

I hope it helps

paperazzo79
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