"Remesh after each shape update" seems unreliable

[cwenner]

Wondering if anyone has tips or comments to use of that option.

I have an axisymmetric model where L-beam cross-sections (which are "fill surfaces") are changed during optimizations. It seems like it would be necessary to check that option so that the elements stay shaped properly when dimensions change dramatically. I'd think this would be very stable... but my optimizations routinely get through 4-12 iterations... and then fail with a "your model is unconstrained" error.

I can change all dimensions to the last set and run a normal static analysis and nothing becomes unconstrained. If I re-mesh and re-start, the optimization typically chugs along find for a while again... and then comes unhinged.

If I do NOT use that feature, the optimization chugs along fine for a while... and then simply provides an unuseful "fatal engine error" message. I presume the elements get stretched or compressed to unacceptable shapes.

Anyone with experience out there that could help?

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[cwenner]

Just adding to my last comment. Optimizations ALMOST always get through more iterations when I do not use the "remesh after each shape change" than they do if I check that option. To me that seems opposite of what should be the case. Seems the code needs to be reviewed. I never have any problem meshing these objects so I'm sure any remeshing should work.

[cwenner · Accepted solution]

Time keeps on ticking but I know the fix (at least now in Creo 2). You must check BOTH boxes. If you check "remesh" AND " Repeat P-Loop Convergence" is works perfectly and reliably for the problems I've done so far.

Pretty goofy though huh? If they are both necessary it seems they should provide just one check box and simply "return yes" to the program for both items.