[Gmsh] [GMSH 2.2.3] - Difficulty with meshing multiple bodies in contact

Christophe Geuzaine cgeuzaine at ulg.ac.be
Tue Aug 12 16:59:50 CEST 2008


Vinay Madhavan wrote:
> Dear Sir/Madam,
> 
> I seem to have a problem with meshing multiple 3D bodies with GMSH 
> 2.2.3. Please find attached a .geo file to create the geometry.
> To quickly explain the geometry and the desired mesh,
> - 2 Bodies which are coplanar at one face for which independent meshes 
> are required , i.e. no merging of nodes/points/lines
> -The surface geometry for which was created with separate points and 
> line with an initial offset.
> -This was then extruded to obtain volumes and translated to the desired 
> location (with one face of each body being coplanar).
> When attempts were made to generate the 3D mesh GMSH would crash, 
> however GMSH successfully generates the 2D mesh.
> 
> I am not sure whether this is a matter of sequence of operation or 
> whether this is a bug. Would be very grateful if you could advise me on 
> a way to get around this.
> 

The Delaunay algorithm triangulates all the volumes at once, so you
cannot use it to mesh degenerate geometries like this one. (The
algorithm will try to mesh the space between the two coplanar surfaces,
and will thus fail.)

You can use the Netgen algorithm for this, as it meshes each volume
separately.



> Please note that this has been tried with version 2.1.1 as well with no 
> success.
> 
> Thanking you
> Sincerely
> Vinay Madhavan
> 
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> gmsh mailing list
> gmsh at geuz.org
> http://www.geuz.org/mailman/listinfo/gmsh


-- 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science
http://www.montefiore.ulg.ac.be/~geuzaine