[Gmsh] Generating mixed element mesh

[Christophe Geuzaine]

On 11 Jun 2013, at 14:15, Kópházi József <j.kophazi at imperial.ac.uk> wrote:

> Dear list members,
> 
> I'm trying to produce a 3D mesh consisting two regions: a region with unstructured tetrahedral mesh and an attached region with structured hexahedral mesh. Obviously, the unstrucutred part needs to include some pyramid elements to facilitate the connection. By using google I realized that the stable release doesn't support this, but according to Christophe Geuzaine answer for an earlier question (https://groups.google.com/forum/?fromgroups#!topic/gmsh-public/mUYykAaFGp4) that the svn version contains an experimental support for this. However, using this, I receive the following error message for every face elements interconnecting the two domains:
> 
> Error   : Cannot build pyramids on non manifold faces
> 
> In order to trace up the problem, I decided to build an extremely simplified model containing two boxes (attached file), but this yields the same error messages and I can not find the error in the geometry.
> 

On non-manifold faces currently your only option is to create the pyramids "inside" the structured mesh, using Trevor's QuadTri feature.

Here's an example:

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> What am I doing wrong?
> 
> Thank you for your help in advance,
> 
> Jozsef
> 
> 
> 
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-- 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science 
http://www.montefiore.ulg.ac.be/~geuzaine