Dear Enmo321,
The first command I suggest to use is "
Geometry > Solid > CleanUp" activating ON ALL options under "
Cleanup Operation" form, not matter your geometry is a pure 3-D solid or 2-D Surfaces. This command will check the solid, and remove any extraneous features which are not part of the actual solid, but may have developed during export from a CAD package or from Boolean operations on it. If a portion of your solid appears inaccurate, or drawn incorrectly, use this command to see if you can remove it. And in general is better to answer NO when FEMAP detect problems like SLIVER GEOMETRY, is better to control yourself the changes.
"Slivers" are small faces that are created because of numerical inaccuracies in Boolean or other solid modeling operations. Typically these faces are much smaller than the other faces that define your solid. While they are small, they can cause great difficulties in meshing. They will often completely prevent a part from being hex meshed. FEMAP will try to removes these surfaces and attempts to restitch your solid without them. This option is only available with Parasolid geometry.
I have just imported in FEMAP a complex surface geometry from CATIA V5 in native format resulting isurfaceface body, yes, but with many patches, with many short edges (plot POINTs to see short edges), making impossible the shell meshing. The resource here I have followed is to re-create surfaces in FEMAP using command "Geometry > Surface > Edge Curves". Previously to get rid of very short edges I used repeatedly the API "CUSTOM TOOLS > GEOMETRY PROCESSING > Break Curves at Middle". To get only ONE curve edge I use command "GEOMETRY > CURVE - SPLINE > POINTS" and finally generate the new surface with "
Geometry > Surface > Edge Curves".
Also, splitting large surfaces in smaller ones will help to get success when either "stitching" or generating "non-manifold" bodies. In this line take a look to comands like "GEOMETRY > CURVE - FROM SURFACE > PARAMETRIC CURVE", this is very useful to split surfaces at points that are not part of the proper surface to split, for instance a point in the edge belonging to other surface.
Yes, under
MESHING TOOLBOX you have plenty of resources for more or less automatic fixing tools like "COMBINED/COMPOSITE CURVES" and "COMBINED/COMPOSITE SURFACES", also "FEATURE REMOVAL" and "FEATURE SUPPRESSION", but I am of those that like ful control of geometry changes and to perform myself all fixing and repairs, you can try and see the best approach to follow, all depends of the geometry complexity, upload a copy of the model and we can take a look, OK?.
Best regards,
Blas.
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Blas Molero Hidalgo
Ingeniero Industrial
Director
IBERISA
48011 BILBAO (SPAIN)
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