[Gmsh] Random behaviour in Gmsh

[Geordie McBain]

> Basically, every time I run Gmsh on the same file I get a different mesh. Sometimes the differernce is very small, but there are times when it quite large. For example, for the same CAD file and meshing parameters, half of the time I am getting a good mesh while half of the time I get one that crashes the solver (because of a few “flat” elements).

Are you optimizing the mesh? This isn't done by default but can be
quite important for subsequent finite element analysis.

 http://geuz.org/gmsh/doc/texinfo/gmsh.html#index-g_t_002doptimize_005b_005fnetgen_005d-34

> Doing some googleing on the subject I found out that this is the intended behaviour of Gmsh and that this randomness cannot be stopped.  However, it is very inconvenient for us, one reason being that we cannot support other users since we cannot reproduce their exact problems.

Dipl.-Ing. A. P. reported a few weeks ago being able to fix the
randomness by meshing from the command line.  I haven't tried it, but
it seems like an easy fix.

 http://www.geuz.org/pipermail/gmsh/2011/006347.html