[Gmsh] create the coarsest 3d hexahedra mesh

Denis Davydov davydden at gmail.com
Wed Mar 27 17:22:43 CET 2013


Dear all,

I just started trying to use Gmsh software.
What I need is a coarsest (for current test almost no refinement) mesh
based on few cuboids. In other words, i want nodes = points (roughly),
 since i plan to do refinement inside FE library. 
The restriction is that i need ONLY hexahedra elements (or quads in 2d).
So these are the options i try to use in the input script: 

   Mesh.Algorithm = 8;//delquad 
   Mesh.Algorithm3D=6;//Frontal Hex
   Mesh.CharacteristicLengthFactor = 999;//want the biggest size

initially i though if I set subdivision to "0" then the set of nodes will be equal to the set of points.
    Mesh.SubdivisionAlgorithm = 2;//Mesh subdivision algorithm (0=none, 1=all quadrangles, 2=all hexahedra
which turned out not to be true, so i use 2. 

With regards to the following 2 i'm not sure, but it seems that if RecombineAll = 0, 
then i have some non-quad element from 2D mesh even when Mesh.Algorithm = 8 !

   Mesh.RecombineAll = 1;
   Mesh.Recombine3DAll = 1;


I was also looking for a way to define a number of devisions per line (in 1D) to set it to "1", 
but could not find this. If there is a way to do it, that would probably solve the problem. 


Thank you in advance,
Regards,
Denis.