Problems about importing into Ansys Workbench

The porous structure generated in Rhino 7 ( saved as a closed subdivision object ) is saved in step format and imported into Workbench. The system will prompt the model to be wrong, and the generated model becomes a broken surface like the model in the graph. Does this mean that the model generated by Rhino 7 is not an entity ?

Hi Cris -

I’m afraid the term “entity” probably has some specific meaning to you that doesn’t necessarily apply to Rhino.

As a quick test, when I export a closed SubD object from Rhino as a STEP file and import that again, I get a closed polysurface that is identical to what the ToNURBS command produces from that SubD object.
How other applications deal with NURBS patches in a polysurface is not something that we know much, if anything, about.
-wim

Thank you Wim.I understand what you mean.I am very appreciate your answering.