Hi Mark,

just in case you are still interested in that topic:
I have briefly tried to find out how this is solved in Joachim Schoeberl's 
netgen. As far as I understand, he uses OpenCascade for his "geometry healing", 
which i have already used successfully to repair those double surfaces. Looking 
into the netgen source, there is a method HealGeometry in occgeom.cpp. I don't 
have the time to delve into the gmsh code an see how this functionality can be 
incorporated there. But since you have already done gmsh programming, it may be 
much less effort for you to try this out.

Best regards,

Matthias

-----Ursprüngliche Nachricht-----
Von: Mark van Doesburg [mailto:[email protected]] 
Gesendet: Montag, 13. September 2010 09:58
An: Zenker, Dr. Matthias; [email protected]
Betreff: Re: [Gmsh] Double surfaces after STEP import

Hello Matthias,

I worked on that code and consider it a complete faillure. In many cases the 
OpenCASCADE algorithms would not find the intersections. The initial version 
was quite simple but at some point I started to stack one workaround on top of 
the other.

Currently I do not have the time to work on another method, but some algorithms 
available in CGAL look promising. But in that case I would probably use BRL-CAD 
to generate the geometry, and importing STEP into BRL-CAD might be sub-optimal.

regards,

Mark

"Zenker, Dr. Matthias" <[email protected]> wrote:

        Hi,

        I have not done FEM calculations for some time (a year or so). The last
        time I did them (using gmsh and Elmer), I had the problem that in
        geometries imported as STEP files (generated by Solidworks), adjacent
        bodies have their own external surface, resulting in double surfaces at
        the interfaces. When I use the mesh generated by gmsh in a FEM
        calculation (I use Elmer), I get no thermal and electrical connection
        because the body meshes are not connected at the interface. There have
        been attempts to clean up double surfaces in gmsh, but I don't know if
        they have come to a success. Could someone of the developpers update me
        on this point?

        Thank you!

        Matthias 

        ----------------------------------------------------------------
        ERBE Elektromedizin GmbH
        Dr.rer.nat. Matthias Zenker
        Dipl. Phys.
        Grundlagenentwicklung / Fundamental Development
        Waldhoernlestrasse 17
        D-72072 Tuebingen
        Phone + 49 (0) 7071 - 755 226
        Fax + 49 (0) 7071 - 755 5226
        E-Mail: <mailto:[email protected]>
        URL: http://www.ERBE-med.de
        ----------------------------------------------------------------


        _____________________________________________________________________
        ERBE Elektromedizin GmbH
        Firmensitz: 72072 Tuebingen
        Geschaeftsfuehrer: Christian O. Erbe, Reiner Thede
        Registergericht: Stuttgart HRB 380137


_______________________________________________
gmsh mailing list
[email protected]
http://www.geuz.org/mailman/listinfo/gmsh

Reply via email to