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-   -   ICEM, holes in swept surface mesh (http://www.cfd-online.com/Forums/cfx/23052-icem-holes-swept-surface-mesh.html)

Roland September 12, 2006 14:08

ICEM, holes in swept surface mesh
 
Hi

Im new to using ICEM, but was using a known-good model from Ansys (that is, meshed well in CFX Mesh). In my application, I have an air intake scoop on the hood of an automobile which is 5mm thick. The scoop was created as a simple loft, and opposing surfaces are not intersecting. For whatever reason, ICEM is leaving several large holes in this scoop, where CFX Mesh does not. I have tried changing tet size, natural size, and a few other things thinking that this was a resolution problem. But, the holes remain while the tet count skyrockets. Is there some functionality I need to use to identify thin surfaces in ICEM, or some other configuration option needed? I believe the geometry is clean...

If it matters for visualization, the test model is a Subaru WRX, with the fairly pronounced hood scoop.

Regards, Roland

Joe September 12, 2006 14:15

Re: ICEM, holes in swept surface mesh
 
Holes are useually caused by:

-Poor surface geometry. -Improper setting of various mesh related tolerances e.g. surface import tolerance. -Improper/Non-use use of Repair geometry > Build diagnostic topology.


Roland September 12, 2006 17:23

Re: ICEM, holes in swept surface mesh
 
Thanks Joe- I will have a look at the tolerances. From what I can tell via various views, the thickness on this scoop is as it should be (and as was handled properly in CFX Mesh). I did leverage the Repair Geometry function post import, but perhaps there are some additional options there I need to consider.

Best, Roland

myron September 13, 2006 08:33

Re: ICEM, holes in swept surface mesh
 
For ICEM - the cleanest way is always to remove unnecessary surfaces. If you previously used CFX mesh, I'm assuming you're meshing for the fluid region - not the solid. So I would keep only the geometry that represents the boundary of the fluid region - deleting the opposite surfaces of the scoop (that are actually bounding what would be the solid volume). That often clears up these types of problems. You can also create thin cuts (Tetra Meshing Parameters) or in the Natural Size settings - ignore wall thickness.


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