[Gmsh] Problem meshing 2 volumes

Christophe Geuzaine cgeuzaine at ulg.ac.be
Wed May 9 11:34:50 CEST 2007


jordi poblet wrote:
> Thanks.
> 
> My doubt has been clarified. I though that only the surfaces included in 
> the surface loop were considered by the algorithm. I could not 
> understand why the second volume was modifying the mesh of the first volume.
> 
> I also had a similar problem with single volumes that are thin (like 
> layers or shells not modelled using surface meshes) but I assumed that 
> it was a normal error and I should use another meshing algorithm like an 
> extrusion. I guess that it can also be related with the small distance 
> between surfaces.

Yes, that's right. Your best bet in such cases is to use the Netgen 
algorithm: due to its hybrid Delaunay/frontal nature, it will never 
(provided that it converges...) change the original surface mesh.


> 
> 
> Jordi Poblet Puig
> 
> 
> 
> On 5/9/07, *Christophe Geuzaine* <cgeuzaine at ulg.ac.be 
> <mailto:cgeuzaine at ulg.ac.be>> wrote:
> 
>     Christophe Geuzaine wrote:
>      >
>      > Use a more recent version of Gmsh (version 2): the new algorithm does
>      > not have this problem.
> 
>     More precisely, the new algorithm should not produce *invalid* meshes.
> 
>     But with the Delaunay the quality might still degrade when the distance
>     is reduced, since the initial mesh is built using all the surfaces in
>     the model (we don't process non-connected volumes separately at the
>     moment with the Delaunay algorithm; we might introduce this as an
>     enhancement later on.)
> 
>     Ch.
> 
> 
> 
>      >
>      >
>      >
>      >
>      >
>      >> Thanks in advance,
>      >>
>      >> Jordi Poblet Puig
>      >>
>      >>
>      >>
>      >>
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>      >
> 
> 
>     --
>     Prof. Christophe Geuzaine
>     University of Liege, Electrical Engineering and Computer Science
>     http://www.montefiore.ulg.ac.be/~geuzaine
> 
> 
> 
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-- 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science
http://www.montefiore.ulg.ac.be/~geuzaine