Hello,

I am working on a static simulation of a formed sheet metal body that is roughly a very large, thin C-channel with flat support ribs placed at intervals inside the C-channel. 

The model is an assembly composed of individual, single-body parts.

The sheet metal body was made using the SolidWorks sheet metal tools and automatically meshes as 2D shells.  The ribs are regular solid bodies, so by default they mesh as solids. 

I made a copy of the simulation in which I converted the ribs to mesh with shells. 

When I run the simulation using the solid ribs, it solves and produces reasonable results.  However, when I initially ran the shell rib version, where the only difference was the type of elements used in the ribs, the study failed, claiming that I had insufficient fixtures in the model.  I am currently trying to debug the shell rib version.

Is there something I am missing that would make the simulation fail?

Thanks,

Katie P.