[Gmsh] simple hexa-mesh

Fabian Braennstroem f.braennstroem at gmx.de
Sun Jun 20 13:44:25 CEST 2004


Hello,

Christophe Geuzaine <c.geuzaine at ulg.ac.be> writes:

> Fabian Braennstroem wrote:
>
>> Hello,
>> I just start using gmsh and wonder if it is able to make a quadrilateral mesh
>> for a
>> square which is rotated. Hopefully the picture helps to get an impression; the
>> square will probably not rotated 45½, so gmsh should just be able to generate a
>> mesh until 30½.
>
> Hi Fabian - You can do it, but not very "elegantly"... Since Gmsh does not have
> an automatic quadrangle generator, you have to divide all the surfaces into
> 4-sided polygons and use the transfinite or elliptic algorithms on those. See
> the attached files for two examples (the first one is simpler, but can lead to
> badly shaped quads for large values of the "angle" parameter).

thanks for those examples it helps a lot. I adjusted the second one a little
bit and think it will be usefull. I would be better if the intersection between
the different regions are smooth. Can Gmsh do that? If not, then I would do the
'coarse' meshing with gmsh and use spline-functions or Bezier (I'm not sure
that this is appropriate, but I will try it) later on.

>>  If gmsh is able to do that, I would like to know where I can find more
>> examples. Is there maybe any kind of wiki or geo-database?
>>
>
> There are some examples in the tutorial/ and demos/ directories. You can
> also find user-contributed examples in the mailing list archives---feel
> free add them (or other ones) in the GetDP Wiki: just create a new page (e.g.,
> "GmshExamples") on http://geuz.org/getdp/wiki/ and attach the files...

I will check them.
Thanks and Greetings!
-- 
Fabian Braennstroem
Duesseldorf/Berlin