> On 12 May 2020, at 11:49, Karin&NiKo <[email protected]> wrote: > > Dear Gmsh Gurus, > > I am facing some troubles with a brep CAD I am trying to mesh with Gmsh. > If I try the meshing default settings, the mesh is being built and Gmsh is > proud to announce that no illegal tet stand in the mesh. *But* if I simply > run "gmsh -check", Gmsh admits that zero volume tets stay in the mesh. So it > is unusable for computation.
There maybe too many messages, but the optimizer indeed reports that there are 6 tets below the quality threshold in volume 2 with the default algo (we should issue a warning if the quality is indeed approaching zero): Info : Optimizing volume 2 Info : Optimization starts (volume = 3.52969e+07) with worst = 0 / average = 0.757222: Info : 0.00 < quality < 0.10 : 212 elements Info : 0.10 < quality < 0.20 : 362 elements Info : 0.20 < quality < 0.30 : 166 elements Info : 0.30 < quality < 0.40 : 222 elements Info : 0.40 < quality < 0.50 : 287 elements Info : 0.50 < quality < 0.60 : 765 elements Info : 0.60 < quality < 0.70 : 3802 elements Info : 0.70 < quality < 0.80 : 7720 elements Info : 0.80 < quality < 0.90 : 4721 elements Info : 0.90 < quality < 1.00 : 4214 elements Info : 321 edge swaps, 0 node relocations (volume = 3.52969e+07): worst = 0 / average = 0.765757 (Wall 0.022079s, CPU 0.022s) Info : 338 edge swaps, 0 node relocations (volume = 3.52969e+07): worst = 0 / average = 0.765884 (Wall 0.0357411s, CPU 0.035583s) Info : 339 edge swaps, 0 node relocations (volume = 3.52969e+07): worst = 0 / average = 0.765909 (Wall 0.0503662s, CPU 0.050068s) Info : 6 ill-shaped tets are still in the mesh > I have succeeded in producing a correct mesh by using the Frontal 3D > algorithm (Mesh.Algorithm3D = 4;). > Perhaps a check of the presence of zero volume elements could be an > interesting enhancement. You can also try Mesh.Algorithm3D = 10; which is (here a bit) faster. Christophe > You'll find all necessary files in the attached archive. > > Regards, > Nicolas > <foo.tar.gz>_______________________________________________ > gmsh mailing list > [email protected] > http://onelab.info/mailman/listinfo/gmsh — Prof. Christophe Geuzaine University of Liege, Electrical Engineering and Computer Science http://www.montefiore.ulg.ac.be/~geuzaine _______________________________________________ gmsh mailing list [email protected] http://onelab.info/mailman/listinfo/gmsh
