damn yes! Shell pressure. I forgot about that one! It really matters!
Thanks for clearing it out. Luckily, this case only has force pull the plate up. No pressure.
nastran-95 d07021a test case
https://github.com/nasa/NASTRAN-95/blob/master/inp/d07021a.inp
TITLE = COMPLEX EIGENVALUE ANALYSIS OF A GAS FILLED THIN CYLINDER
SUBTITLE = NASTRAN DEMONSTRATION PROBLEM NO. D07-02-1A
Left is CFLUID4, right is CQUAD1.
Red cone is SPC1
Are you planning on adding Nastran solver to FEM ?
hfcNASTRAN95
FreeCAD workbench for pre/post processing for NASTRAN95
https://forum.freecadweb.org/viewtopic.php?f=9&t=48695