So I'm trying to run a fatigue analysis on a pressure vessal. I've got a nonlinear analysis that is run over 7.5 seconds, and has a "base pressure" and a "peak pressure". That non-lin analysis runs perfectly.... lets call it "Nonlinear 2". It's an axi-symetric 2d simulation, fwiw.
So I created a fatigue study, and I go to "loading", right click and select "Add event".
A window pops up that says:
"You need one or more static, nolinear [sic] or linear dynamic to perform Fatigue Analysis."
So I've got my "Nonlinear 2" analysis that works perfectly, but for whatever reason Fatigue doesn't like it. I'll try running non 2-d simplification, but in the meantime I'd still like to know for sure if that's the issue.
Additionally, I'm finding it all but impossible to apply S-N curves to the materials.... I can create new materials with S-N curves, but my EPDM managed materials won't let me save the S-N curves to the material definitions. Additionally, you don't seem to be able to edit the S-N data in the generic materials interface....seems like you can only do it by accessing the material THROUGH a valid fatigue study (which seems ridiculous).
Am I missing something here?
(yet again frustrated)