[Gmsh] surface mesh, connect the faces of a compound

[David Colignon]

On 22/09/15 08:03, Bernd Hahnebach wrote:

> Hi David,
>
> thanks for the fast reply. It is what I would like to have connect the faces if they share an edge. Yes the provided option
> seams to do the trick.
>
> -string "Geometry.OCCSewFaces=1;"
>
> It worked on the simple provided part compound_of_faces.step and on one with 10 faces beam-10faces.step. With bothe the FEA
> worked out very well :-) On a more sophisticated part mechanical-part.step it seam to work out too but I get non positive
> jacobian during FEA, but that seams to be another part of the story.


Hi,

for more complicated parts, you should also open your step file directly with Gmsh, and try the other options "Remove 
degenerated edges and faces", "Remove small edges", ... in Tools -> Options -> Geometry -> General and also look at the Info 
messages.

Regards,

Dave

>
> Downloadlink is still:
> https://cloud.woelkli.com/public.php?service=files&t=1cfd13febed7694726b902cdb36476d4
>
> I need to test on more examples. I will report back.
>
> kind regards bernd
>
>
>
>
> Zitat von David Colignon <david.colignon at ulg.ac.be>:
>
>>
>> Hi Bernd,
>>
>> can you try with adding    the
>>
>> -string "Geometry.OCCSewFaces=1;"
>>
>> option ?
>>
>> This should work with relatively simple geometries, i.e. faces sharing a common line.
>>
>> Regards,
>>
>> Dave
>>
>> --
>> David Colignon, Ph.D.
>> 1er logisticien de recherche
>> Université de Liège
>> ACE - Applied & Computational Electromagnetics
>> Sart-Tilman B28
>> 10, Grande Traverse
>> 4000 Liège - BELGIQUE
>> Tél: +32 (0)4 366 37 32
>> http://www.ulg.ac.be/nic4
>>
>> On 21/09/15 19:25, Bernd Hahnebach wrote:
>>> Hi there,
>>>
>>> This is my first post to the mailing list so I may introduce myself first. The "identifier" given to
>>> me by my parents is Bernd and this corresponds to what most people call myself. The bred to feed
>>> myself an my familiy I earn in an engineering office near Zuerich in Switzerland. I'm structural
>>> engineer in the building industry. In my spare time I develop on the FEM Workbench and on the Arch
>>> Workbench of the parametric open source cad plattform FreeCAD. This is why I'm gone write to this list.
>>>
>>>
>>> FreeCAD uses for internal parametric surface and solid meshing netgen. AFAIK due to licence
>>> incompatibility between FreeCAD and GMSH it has never been an option to use GMSH instead. But there
>>> exists a FreeCAD macro which uses the GMSH installed on ones computer for meshing. Most users mainly
>>> use this GMSH macro for meshing their models including myself. The macro exports a *.step meshes
>>> with GMSH and imports the *.unv mesh back into FreeCAD. Babbled enought,the important part of the
>>> post ...
>>>
>>>
>>> I run into trouble with meshing compunds of faces. The faces where not connected to each other and
>>> thus a Finite Element Analysis will fail to work without manual connection off all the faces of the
>>> compund. As a example a very simple compund of just two faces is taken.
>>>
>>> mesh command:
>>> gmsh compound_of_faces.step -3 -format unv -o compound_of_faces.unv -algo netgen -clmax 100,00
>>> -order 2 -optimize
>>>
>>> gmsh --version
>>> 2.8.5
>>> on Debian Jesie
>>>
>>> I was wondering if it is possible to tell GMSH to mesh a connected Surface Mesh of a compund of faces?
>>>
>>> The files could be downloaded here:
>>> https://cloud.woelkli.com/public.php?service=files&t=1cfd13febed7694726b902cdb36476d4
>>>
>>>
>>> Kind Regards and thanks to all people who have ever contributed to GMSH development.
>>>
>>> Bernd
>>>
>>>
>>>
>>> _______________________________________________
>>> gmsh mailing list
>>> gmsh at geuz.org
>>> http://www.geuz.org/mailman/listinfo/gmsh
>>
>
>
>