On 22 Feb 2014, at 12:01, Jaensson, N.O. <[email protected]> wrote:
> Dear Gmsh users, > > I use Gmsh to generate quite simple 2nd-order 2D meshes, where one of the > boundaries is part of a circle. I would like to perform a mesh convergence > study of my FEM code, so I would like to be able to start with a coarse mesh, > which is subsequently uniformly refined a number of times. If I load my .geo > file into the GUI, I generate the coarsest mesh by subsequently clicking "2D" > in the "Mesh" section, and then "Set order 2", this aligns the midpoints of > the quadratic elements nicely on the circle. If I now click "Refine by > splitting", a first order, refined mesh is created. Clicking "set order 2", > converts this into a second order mesh where the midpoints of the quadratic > elements align nicely with the circle again. The problem is that I have no > idea how to do this using the command line, which I mainly use to generate > meshes from within the FEM code. > > I am able to uniformly refine my mesh using the command line, by following > the suggestions in this thread: > > http://www.geuz.org/pipermail/gmsh/2013/008004.html > > However, the midpoints of the quadratic elements on the boundary are just > inserted between the existing nodes, and not on the circle. I guess since the > .msh file is used, the geometric information is lost, and new nodes are just > inserted between the existing nodes. > > Since the GUI is able to do this, I expect that it is also possible from the > command line. Any help would be much appreciated! > Hi Nick, Create a file that contains something like this: Merge "demos/sphere.geo"; Mesh 2; SetOrder 2; Save Sprintf("mesh%03g.msh", 0); For i In {1:3} RefineMesh; SetOrder 2; Save Sprintf("mesh%03g.msh", i); EndFor Then run it from the command line with "gmsh myscript -" Hope this helps, Christophe > Kind regards, > Nick > > > > _______________________________________________ > 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
