[Gmsh] Extrusion and Standard Volume together do not mesh

[Christophe Geuzaine]

Wladimyr Mattos C. Dourado wrote:
> Hi Guys
> 
> What can I say about after three years using gmsh? It's really a very
> nice code! Then I send congratulations once more for all developer team!
> I have three students which are working with gmsh and AOMD to develop a
> new thing. I hope early we will give a good contribution for the
> gmsh-AOMD community.
> 
> Now I have a problem. I attached a .geo file which is a 3D mesh
> generated around a wing which profile is given by many points. I
> extruded the mesh near the body to generate a nice mesh for boundary
> layer, and I created a standard volume to be mesh with tetrahedra
> outside this regions as you can see. But: Huston, We have a problem!
> When I put gmsh to generate the 3D mesh, only the mesh from extrusion is
> performed. I can't see any volume outside the extrusion region. If I
> create the outside volume first, the mesh generator crashes.  Before I
> tried to generate the outside volume by extrusion whitout success, too
> :-( Could somebody help me to solve this problem?

Hi Wladimyr - In "wing.geo" you recombine the extruded mesh, so there
are quads on the boundary--and Gmsh's unstructured algorithm only
generates tetrahedra (the algorithm should create pyramids at the
interface but that's not implemented).

One solution is to remove the "Recombine" commands, so that you have
triangles/tetrahedra everywhere. A better solution is probably to just
extrude everything (this works nicely: cf. attached file "wingex.geo").

Christophe

-- 
Christophe Geuzaine
Applied and Computational Mathematics, Caltech
geuzaine at acm.caltech.edu - http://geuz.org
-------------- next part --------------
A non-text attachment was scrubbed...
Name: wingex.geo.gz
Type: application/x-gzip
Size: 3337 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20050412/dea0169d/attachment.gz>