Hi,
I’m experiencing some unexpected results when applying a nonlinear Pre-Load with its option Auto compute activated. I think it does not compute the Preload direction correctly and at some point of the process the preload deviates.
¿Has someone experience that? ¿is autocompute just for Preloading with a Static Linear step?.
Regards
Regards
Enabling this option internally just adds the *PRE-TENSION SECTION keyword without the data line where vector can be manually specified:
If no such vector is defined by the user, it is calculated automatically as the mean of the normals away from the elements whose faces belong to the surface (volumetric case) …
Then it generates linear MPC:
Internally, the nodes belonging to the element face surface are copied and a linear multiple point constraint is generated between the nodes expressing that the mean force is the force specified by the user (or similarly, the mean differential displacement is the one specified by the user).
Those description don’t seem to suggest any effort done by CalculiX to update the pre-tension direction during geometrically nonlinear analyses. Especially since in Abaqus it requires a separate parameter:
Thanks Fea,
Then it is not a Prepomax issue. At some point those elements away from pretension surface might be deformed and mess the convergence.
Would there be any way I copuld open this Pmx file with the new version?
It was share by Juan on the calculix forum but now doesn’t open with Prepomax. Something has change
His boltpipe4_calculix_1a.pmx file is from v2.0.3. It opens for me in v2.2.0 and v2.2.10. There’s just a warning about 1 removed user keyword. His file is from a version where *TRANSFORM was not implemented so he added it manually.
