[Gmsh] problem with the meshing of a brep file

Romain MARECHAL rmarecha at utc.fr
Fri Aug 21 16:47:49 CEST 2009


Good afternoon,

I'm sorry for the first mail I have previously sent because I solved the 
described problem. Here are the explanations :

First, I use the Guide User Interface (GUI) for meshing and refining. In 
fact, when I refined with the "Refine" button, the non physic elements 
appear. But if I mesh again in 2D, the problem disappear and I can also 
mesh in 3D (no error message in Message Console)...

I'm sorry for the previous mail. I think that if I use a geo script 
(with specified length element), there will be no problem. I put the 
steps that allowed me to solve the problem :

With GUI :

1. I mesh the geometry in 2D (mesh_once.jpg)
2  I refine (mesh_refined.jpg)
3  I mesh again (F2 button, mesh_refined2.jpg)
4 I mesh in 3D (F3 button, mesh_refined3D.jpg)

Thank you for your attention and sorry again for the disturbance,

Best Regards,

***************************************************
* Romain MARECHAL                                 *
* Doctorant                                       *
* Laboratoire de Mécanique Roberval               *
* Division Acoustique et Vibrations Industrielles *
* Université Technologique de Compiègne           *
* Tél. : 03.44.23.48.76                           *
*************************************************** 



Romain MARECHAL a écrit :
> Good afternoon,
>
> I have some problem in Gmsh with the meshing. I import a geometry (a 
> brep file, see geom.jpg) from FreeCAD. This geometry is the union 
> between a torus and a cylinder. It describes a closed volume in order 
> to mesh in 3D. When I meshed this geometry in 2D once, there is no 
> problem (see mesh_once.jpg) but when I refined, non physic elements 
> appear (see mesh_refined.jpg).
>
> I want to know if this problem is in Gmsh or in the Boolean operation 
> in FreeCAD (union) ?
>
> On the other hand, when I tried to mesh this volume in 3D, this 
> message appears in the meesage console :
>                                Error   : Self intersecting surface 
> mesh, computing intersections (this could take a while)
> There is no problem when I exported only the torus part. I can mesh it 
> in 2D or 3D.
>
> I join the brep file if you want to see it. I have the last version of 
> Glmsh.
>
> Thanks in advance,
>
> Best regards,
>
>
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