[Gmsh] Problem meshing 2 volumes

[jordi poblet]

Dear all,

I attach a file with an example where I am meshing two unlinked volumes (no
common points, lines or surfaces). If I mesh both of them when they are
largely separated (for example dlx = 0.5) I obtain correct meshes. However,
if I mesh them when are separated by small distance (dlx = 0.01) the quality
of the mesh in the first volume is very poor. The two pictures of the
surface 4 of the first volume are very different and I would expect the same
mesh or at least a mesh with the same quality (mesh1.jpg, distance between
volumes 0.5 and mesh2.jpg distance between volumes 0.01). If I only mesh the
first volume (even with small distance dlx = 0.01), the mesh is correct.

I have not got this problem if I use netgen option (Mesh.Algorithm3D = 4; ).
I have found the same behaviour using a Linux version or a Windows version
of Gmsh. Moreover, the following message is written for the cases of poor
mesh quality:

.....

Info : 140/395: Face 291 311 340

Info : Intersections left (the face contains 0 initial faces, divided in 5
points)

Info : The face is divided in 8 points (simplexes added=23, deleted=9)

Info : Recoverable face (9 <--> 9=2*(8-1)-5)

Info : 141/395: Face 297 311 340

......

Does someone know the causes of this strange behaviour? What should I do?

Thanks in advance,

Jordi Poblet Puig
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