NASTRAN Effective modal mass
NASTRAN Effective modal mass
(OP)
Hello,
I am doing a normal modes analysis of a 3D wing. I used a modified version of input bdf file from cfd4aircraft.com. The file is attached herewith. I want to output the effective modal mass participation in the .F06 file. I added the line "MEFFMASS(ALL) = YES" in the case control data section. But NASTRAN does not print out the modal mass participation in the output file. Could anyone kindly help me where I am wrong? Thank you!
I am doing a normal modes analysis of a 3D wing. I used a modified version of input bdf file from cfd4aircraft.com. The file is attached herewith. I want to output the effective modal mass participation in the .F06 file. I added the line "MEFFMASS(ALL) = YES" in the case control data section. But NASTRAN does not print out the modal mass participation in the output file. Could anyone kindly help me where I am wrong? Thank you!





RE: NASTRAN Effective modal mass
Replace the mefmass all line by this one and see if it print out the results in the .f06 file
MEFFMASS(PRINT,GRID=0,PARTFAC,MEFEM,MEFEW,FRACSUM,SUMMARY) = YES
Seif Eddine Naffoussi, Stress Engineer
www.Innovamech.com
33650 Martillac û France
RE: NASTRAN Effective modal mass
Thank you for the reply. I tried your suggestion, but it does not work. I am using a student 2013 edition. Might that be the reason?
RE: NASTRAN Effective modal mass
I managed to run the input file directly and get the modal effective mass? Please see below picture.
Regards,
Tuw
RE: NASTRAN Effective modal mass
I figured out the problem with help from MSC Tech Support. It is actually a limitation with the student edition. This command needs to be put through Direct text input and Patran does not write out direct text input in .bdf file for student version. However, the same file does work when submitted directly to Nastran.