I am working on a structure consisting of beam like members, I have performed fully mapped mesh with Solid HEX elements. I want to extract NQM forces at some planes across the length of the beams. To do this, I used the freebody tool which works really well in a linear static analysis (SOL101). However, when I perform a frequency response analysis (SOL108) the freebody tool doesn't work anymore. On the Nastran Output Requests, I request Nodal force balance outputs to get the nodal forces data. Does the freebody tool work on frequency response analysis? Is there any other way to extract the NQM forces from the Solid elements?
There is a “trick” to getting this to work. You need to have PARAM,DDRMM,-1 in your Nastran input file.
To do this in FEMAP, enable the “DDRMM off” option in the NASTRAN Bulk Data Options dialog box:
From the NX Nastran Quick Reference Guide entry for “GPFORCE” in the Case Control section:
Remark 3. PARAM,DDRMM,-1 is required in the modal solution sequences 111, 112, 146, and 200.