CEM ALBUKREK wrote: > Hello Christophe, > > I have been using Gmsh successfully to build complex tet meshes as input > to OpenFOAM. To give you a sense of the complexity attached is a picture > of a typical surface mesh, which is an assembly of NAS and STL files > combined into one closed volume using some scripts I developed. You have > warned on your website that GMSH is not so good at large meshes from > STL's; what threshold (# of tets) did you have in mind? I am able to go > as far as the 32 bit memory allows me to at this point. May be the trick > is the application of effective surface mesh smoothing techniques before > moving onto volume meshing... > > One issue with CFD is that one can march an unsteady (varying time) > simulation only as fast as the smallest tetrahedron allows; i.e. > > velocity * time_step <= tet size > > for each one of the tetrahedra. > > Sometimes small elements are unavoidable no matter how great a surface > mesh one puts together. One way around the problem is to blindly erase > the tetrahedra smaller than a threshold and run the flow simulation > around these tiny blockages, which are too small to affect the bulk > flow. I would like to implement a little sub-routine to do the same > thing with GMSH. For instance we have the mesh quality filters for beta, > gamma & theta. In a similar fashion I would like to put one for the size > (or volume) and also be able to click delete. Do you see any problem > with this?
Hi Cem - You could do this interactively: 1) select a size range for the elements in Options->Mesh->Visibility 2) in the mesh menu select "Delete" 3) select all the visible elements with the mouse (Ctrl+LeftButton to start a rectangular selection area, LeftButton to finish) > May be FEM solvers could benefit from this kind of feature as > well knowing tiny bubbles are not uncommon in molded plastics and cast > metals. > > What do you think? > > -- > CEM M. ALBUKREK, PhD > Computer Aided Engineering Design Consultant > Tel: (857) 234-1035 > > ------------------------------------------------------------------------ > > > ------------------------------------------------------------------------ > > _______________________________________________ > 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
