[Gmsh] handling stp file (example attached)

Christophe Geuzaine cgeuzaine at ulg.ac.be
Sat Feb 18 10:51:37 CET 2012


On 17 Feb 2012, at 15:53, Sangpil Yoon wrote:

> Oh....Thanks for your input....
> i thought i read all options in the manual, but clearly i did not.
> 
> "Geometry.OCCSewFaces=1" worked partially..... 
> in some other tests, i still have duplicated nodes..
> 
> my question now is that how to use "Coherence Mesh"
> 
> i now know "Coherence" only works for generic .geo file.
> 
> once i generate mesh, though, if i have duplicate nodes, i should be able to clear it with  "Coherence Mesh" command.
> 
> Could you please make some comments on it?
> 

You can either do:

Merge "file.msh";
Coherence Mesh;

or force meshing within the script:

// geo definition
Mesh 2;
Coherence Mesh;


> how about all gmsh experts here? 
> is there someone who has some experience on the issue?
> 
> as always thank YOU very much well in advance.
> 
> 
> On Fri, Feb 17, 2012 at 12:31 AM, Christophe Geuzaine <cgeuzaine at ulg.ac.be> wrote:
> 
> Hi,
> 
> "Coherence" only applies to native .geo models. Geometry.OCCSewFaces seems to repair your open cascade model:
> 
> =====
> Mesh.CharacteristicLengthFactor=0.25;
> Mesh.Algorithm=1; // 2D mesh algorithm  (1) MeshAdapt (default)(5) Delaunay (6) Frontal
> Mesh.ElementOrder=1; // 1=linear elements, N (<6) = elements of higher order
> Geometry.OCCSewFaces = 1;
> 
> Merge "Volume1.STEP";
> =====
> 
> 
> 
> On 16 Feb 2012, at 23:54, Sangpil Yoon wrote:
> 
> > Dear Gmsh experts;
> >
> >
> > previous post was a kind of general question....
> >
> > here i attached a .STEP and .geo file
> >
> > i did the following in command line
> >
> >
> > > gmsh test.geo -2 -format msh -o test.msh
> >
> >
> > the geometry is pretty simple; a cylinder shape on one side of a box.
> >
> > you will see duplicate nodes are there.....because there ARE duplicate lines and points.
> >
> > did I do something wrong in using .geo file?
> >
> > Or, do i need to do something before exporting .STEP file?
> >
> >
> > any comments are welcome.
> >
> >
> > NOTE: If i do the same thing in the following manner, no duplicate nodes are found.
> >
> > 1. read .STEP file
> > 2. save it as .geo file
> > 3. add one line 'Coherence' at the end of .geo file
> > 4. do mesh
> >
> > i strongly believe I am not properly using .geo file or command.....
> >
> > <test.zip>_______________________________________________
> > gmsh mailing list
> > gmsh at geuz.org
> > http://www.geuz.org/mailman/listinfo/gmsh
> 
> --
> Prof. Christophe Geuzaine
> University of Liege, Electrical Engineering and Computer Science
> http://www.montefiore.ulg.ac.be/~geuzaine
> 
> 
> 
> 

-- 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science 
http://www.montefiore.ulg.ac.be/~geuzaine