CEM ALBUKREK wrote: > Dear Christophe, > > I have a quick question on extruding closed NAS surfaces, with multiple > part ids (PIDS). What I mean by this kind of mesh is that a given closed > NAS mesh consists of unclosed shell partitions. I have been able to > build nice volume meshes around such surface mesh data successfully > using GMSH. So somehow GMSH must be interpreting the vertices at the > seams of the PIDS correctly when volume meshing. In fact, there is no > duplicate vertex at the seam in the NAS file definition. > > Unfortunately, I do not see consistent behaviour with surface extrusion > from the same mesh, receiving "could not find extruded vertex" error at > the seams of PIDS. I think the problem is that GMSH interprets each PID > (shell) independently of its neighbors when applying extrusion. Hence > the vertex normals can not be computed correctly at the seams. Am I > correct with this? Do you see a way around, or could you point me to the > section of the code which might require some improvement for this? I > think vertex normal calculation at shared edges needs the tweak... > > Attached is a sample file pair (.geo and .nas) for you to observe the > problem. At the header of the .geo file there is a switch to turn off > the extrusion (boundary layer mesh) to verify the volume meshing works > well. Please let me know how I can tackle the issue. Note that I have > tested the same case for which the NAS file has one single PID - one > closed shell - and extrusion works... >
We'll have a look. > Thank you. > > Cem > > > ------------------------------------------------------------------------ > > _______________________________________________ > gmsh mailing list > [email protected] > http://www.geuz.org/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://www.geuz.org/mailman/listinfo/gmsh
