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Joe March 9, 2005 12:47

Geometry Error Generation
 
Hi, I am trying to import a yacht hull model made in Pro/E. I save the IGES file as surface and when i try to generate the surface mesh there is a problem with the surfaces.. Problem: Topology error detected in CAD model.

CAD edge referenced

1 times by faces. Result: Model invalid for meshing. Cause: Invalid model.

I dont know what it means! I tried to change my model but still the same results. Does anyone has any suggestion?

Thanks

Glenn Horrocks March 9, 2005 16:18

Re: Geometry Error Generation
 
Hi Joe,

I would recommend using Parasolid to export the geometry rather than IGES. IGES is only an approximation of the surface and hence can generate mismatched edges and gaps. Parasolid can represent the exact geometry.

Glenn Horrocks

Joe March 14, 2005 08:07

Re: Geometry Error Generation
 
Thanks for your answer! I tryed doing what you said but Pro/E doesnt have parasolid extensions as an export. Also i am using CFX 5.7 without the CFX-Build and i am trying to import into ANSYS Workbench the IGES file.I was told that i can do that as a solid-IGES but in this way doesnt work at all!

Do you have any suggestions? Thanks in advance

Glenn Horrocks March 14, 2005 16:43

Re: Geometry Error Generation
 
Hi Joe,

As I said, IGES represents complicated surfaces (and I am sure your yacht hull is a complex surface) by an approximate method and is therefore to be avoided if possible. If ProE does not support parasolid then it should support other formats, maybe STEP or ACIS. There is a bit of trial and error in it, you have to find a good match for ProE and WB. Only use IGES as a last resort.

Glenn Horrocks

R408 March 15, 2005 22:57

Re: Geometry Error Generation
 
Hi Job,

In my experience, i have faced same problem before. Since the old version of Pro/E didn't able to export Parasolid (*.x_t) file expect for Pro/E wildfire version. Therefore, you have to export the CAD model in STEP format to CFX since Parasolid and STEP format is better for I/O to other CAD and CAE software.

I use ANSYS/ICEM to generate mesh model for CFX5.7. Sometimes, I need to use UG to simplify the CAD model and then repair the CAD model by CADfix. If your model is complicated, i suggest you should simplify the CAD model by UG first and then fix other geometry problems by CADfix.

Raymond


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