[Gmsh] Combine different meshes in same geometry

Marco Cargnelutti marcocargne at gmail.com
Wed May 23 11:20:08 CEST 2012


Thanks for your replies.
Maybe I'm doing something wrong, for testing the merge function I'm
doing the following steps:

1. Create "reticula_part.geo" with geometry, selecting Mesh->2d and
saving the triangular mesh in "reticula_part.msh" (this will be the
mesh created with another software called Reticula which creates
triangular mesh with non obtuse triangles).

2. Create "geo_final.geo", calling Merge "reticula_part.msh", define
geometry, Transfinite lines and surfaces, recombine (for quadrangles).
Select Mesh->2d. It works but there's a mismatch (look figure).

I've not defined the surface of the already merged, because it will
produce another mesh over it.

I've tried like you suggested the CreateTopology; in a new file that
merges the two .msh file but it fails and tells me "Fatal   : Wrong
list index (read)".

For the Extrude command I think it's like you said but it's not a big
problem in the end, it can be done with matlab.

The figure of the correct mesh is done with a unique mesh command on a
single.geo file on gmsh, unfortunately I need non obtuse triangles in
the mesh and gmsh doesn't have this option (or has it ????).

Thanks again.

2012/5/21 Cristóbal Bertoglio B. <cabertog at ing.puc.cl>:
> hi
>
> did you call the command "CreateTopology;" after merging the meshes in
> your .geo file?
>
> As far as I know you cannot extrude surfaces if they don't come from
> the geometry commands in gmsh, but maybe now they change it ?!
>
> best
>
> Cristobal.
>
> 2012/5/20 Marco Cargnelutti <marcocargne at gmail.com>:
>> Dear gmsh users,
>>
>> I'm using gmsh to create a 2d geometry that will be meshed partly with
>> quadrangles (let's say an external square with an hole) and partly
>> with triangles (the internal hole).
>>
>> The triangular mesh is made with another mesh generator so I merge the
>> related .msh file in the .geo file with
>>
>> Merge "triangular_part.msh";
>>
>> then I make the part with quadrangles with "Mesh->2d" in GUI.
>>
>> The first problem is that when the quadrangles mesh is created there's
>> a mismatch between the border points of the internal hole (already
>> mesh) i.e. the internal hole already meshed is not taken account of
>> when the quadrangles mesh is created.
>>
>> The second problem is that I don't find a way to Extrude the merged file in 3d.
>> It works for the geometry and the quadrangles mesh but fails with the
>> merged mesh.
>>
>> If somebody could help me that'll be greatly appreciated :)
>>
>> Thanks a lot in advance!
>>
>> Marco
>>
>> _______________________________________________
>> gmsh mailing list
>> gmsh at geuz.org
>> http://www.geuz.org/mailman/listinfo/gmsh



-- 
Marco Cargnelutti
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