Hi David, Thanks for the quick answer. The stl importation crashes with the stl file or a msh file obtained from the stl, but I guess that's because my stl is too fine (214K elements), I'll try again with a coarser mesh. As far as the prism extrusion is concerned,it works well and after recombining, the prism look perfectly fine on a curved surface, except that I get errors telling me that the prisms are degenerated. Is it an unnecessary warning or should I be worried? I also have a bonus question if you don't mind. When I generate the extrusion of the surfaces and put them on a list surf[], is it possible to access the edges and vertices of the top surfaces to define the volume above? I could extrude the edges and vertices too but it would mean that some entities would be duplicated. Best regards Julien ________________________________________ De : David Colignon [[email protected]] Date d'envoi : vendredi 11 décembre 2009 14:40 À : Hoessler, Julien Cc : [email protected] Objet : Re: [Gmsh] stl and prism extrusion
On 11/12/09 15:00, Hoessler, Julien wrote: > Good afternoon all, > First of all, thanks for writing this code, I'm using it a lot to generate > 2D/3D meshes for DNS and stability analysis. I was wondering if it is > possible to extrude a layer of prisms using the surface normals instead of a > specific direction. I need to generate a layer of prisms out of a wall which > is curved and there is more than 80 degrees of angular difference between the > two extreme locations of the surface (it is smooth, but twists a bit like a > sinh). Hi Julien, it is still experimental and quite hidden in the documentation ( http://www.geuz.org/gmsh/doc/texinfo/gmsh.html#Structured-grids ), but you can try: Extrude { Surface { expression-list }; layers } which extrudes a boundary layer along the normals of the specified surfaces (if they are smooth and do not form acute angles). > My second question is about the stl importation. I have a stl file which is a > 3D box that I can read and visualise without problems, but I'd like to remesh > it The undocumented "Compound Surface" command is also very experimental, but you can try the attached file (reparam.geo) which here use a .msh file but should also work with a .stl file. , mesh the volume inside and split the box surface to assign different physical groups for boundary conditions (and add a layer of prisms on one of the surfaces). Is it possible with Gmsh? I've searched through the questions in this mailing list, do I need the opencascade support for this? Regards, Dave -- David Colignon, Ph.D. Collaborateur Logistique du F.R.S.-FNRS CÉCI - Consortium des Équipements de Calcul Intensif ACE - Applied & Computational Electromagnetics Sart-Tilman B28 Université de Liège 4000 Liège - BELGIQUE Tél: +32 (0)4 366 37 32 Fax: +32 (0)4 366 29 10 WWW: http://hpc.montefiore.ulg.ac.be/ Agenda: http://www.google.com/calendar/embed?src=david.colignon%40gmail.com _______________________________________________ gmsh mailing list [email protected] http://www.geuz.org/mailman/listinfo/gmsh
