Dear Simone, Can you try with the latest snapshot to see if it's better?
Christophe > On 17 Dec 2018, at 17:41, Simone GREMMO <simone.gre...@umons.ac.be> wrote: > > Dear Christophe, > as you asked in your previous email, I have been testing the newly > implemented quad-boundary recovery in Gmsh (at that time it was the > development version, future 4.0.5 or 4.1). > > I found that Gmsh works fairly well, succeeding to generate a valid mesh with > sufficient overall quality (a few ill-shaped elements may be present > depending on the geometry configuration). > However, in some cases, the resulting mesh has a negative cell. All the > failing cases have one negative cell only, this cell always being a flat > pyramid (see attached picture). It looks like the vertex relocation cannot > move the top of the pyramid inside the volume. > > Does anyone have reported a similar behaviour? > If necessary, I can provide you with a failing test case. > > Regards, > Simone G. > From: Christophe Geuzaine <cgeuza...@uliege.be> > Sent: Monday, November 12, 2018 3:33:25 PM > To: Simone GREMMO > Cc: gmsh@onelab.info > Subject: Re: [Gmsh] Gmsh-4.0.4 Volume mesh issue > > > Dear Simone, > > Indeed, Gmsh 4.0.0 -> 4.0.4 do not have the ability to automatically create > hybrid tetrahedral+pyramidal meshes (your surface contains quadrangles). > > The latest snapshot (future Gmsh 4.0.5 or Gmsh 4.1) has a new algorithm to > generate such meshes, similar but more general to what we did in Gmsh 3. Give > it a try and let us know how it works out for you? > > Christophe > > > > On 12 Nov 2018, at 14:38, Simone GREMMO <simone.gre...@umons.ac.be> wrote: > > > > Dear all, > > I have just downloaded the last version of Gmsh (4.0.4), but I am facing a > > problem with the generation of a "simple" volume mesh. > > > > I would like to mesh a volume delimited by a surface mesh in .msh format, > > but it looks like Gmsh cannot create the volume mesh. > > Error Message is : > > ..... > > Info : Boundary Recovery... > > Info : Writing to GRegion... > > Info : Reconstruct time : 0.116395 sec > > Error : No tetrahedra in region 5 > > Info : 3D point insertion terminated (3195 points created): > > Info : - 0 Delaunay cavities modified for star shapeness > > Info : - 0 points could not be inserted > > Info : - 0 tetrahedra created in 1.6e-05 sec. (0 tets/sec.) > > Error : No tetrahedra in region 5 > > Info : Done meshing 3D (0.133228 s) > > Info : 4857 vertices 6617 elements > > Error : ------------------------------ > > Error : Mesh generation error summary > > Error : 0 warnings > > Error : 2 errors > > Error : Check the full log for details > > Error : ------------------------------ > > > > I am attaching the .geo file I have created as well as the surface mesh I > > used. To launch the mesh generation I run the command: > > gmsh-4.0.4 createGeom.geo -3 -o volumeMesh.msh > > > > Note that the same test case is successfully meshed using Gmsh version > > 3.0.6. > > > > Do you have any suggestion on how to solve the problem? > > Is it possible that the surface mesh, containing both triangles and > > quadrangles is at the origin of the problem? > > > > Thanks in advance for your suggestions. > > Regards, > > Simone G. > > > > <createGeom.geo><surfaceMesh.msh>_______________________________________________ > > gmsh mailing list > > gmsh@onelab.info > > http://onelab.info/mailman/listinfo/gmsh > gmsh Info Page > onelab.info > Gmsh is a free 3D finite element mesh generator with built-in pre- and > post-processing facilities. This list is for questions and discussions about > Gmsh features, resources, bugs, and so forth. Useful links: Gmsh homepage > (for documentation, downloads, etc.); gmsh-announce mailing list (for > announcements about new Gmsh releases and major bug fixes - you probably want > to subscribe to that, as well) > > > — > Prof. Christophe Geuzaine > University of Liege, Electrical Engineering and Computer Science > http://www.montefiore.ulg.ac.be/~geuzaine > > Free software: http://gmsh.info | http://getdp.info | http://onelab.info > > <negCell_.jpg> — Prof. Christophe Geuzaine University of Liege, Electrical Engineering and Computer Science http://www.montefiore.ulg.ac.be/~geuzaine _______________________________________________ gmsh mailing list gmsh@onelab.info http://onelab.info/mailman/listinfo/gmsh
