# [Gmsh] Periodic boundary

Jehanzeb Hameed jehanzeb.hameed at gmail.com
Sun May 23 07:03:24 CEST 2010

```Thanks for replying. This does indeed give matching meshes on planes
z=0 and z=1. However, I also want matching on atleast two other
planes, e.g. x=0 and x=1. Is that doable?

Thanks,
-Jehanzeb

On Sat, May 22, 2010 at 1:22 AM, Ruth V. Sabariego
<r.sabariego at ulg.ac.be> wrote:
> You can extrude the surface and remove the volume obtained in order to take
> into account
> the other elements inside your 3D cube.
> E.g.:
>
> Point(1)={0,0,0};
> Point(2)={1,0,0};
> Point(3)={1,1,0};
> Point(4)={0,1,0};
>
> Line(1) = {1,2};
> Line(2) = {2,3};
> Line(3) = {3,4};
> Line(4) = {4,1};
>
> Line Loop(1) = {1,2,3,4};
> Plane Surface(1)={1};
>
> vol[]=Extrude{0,0,1}{Surface{1};};
> Delete {Volume{vol[1]};}
>
> The two surfaces on xy planes have the same mesh.
>
> Regards,
> Ruth
>
> On 22/05/10 01:20, Jehanzeb Hameed wrote:
>>
>> Hello,
>>
>> I am trying to create a 3-D cube mesh, such that the opposite faces
>> along x and y directions have identical surface meshes, which will be
>> useful for me to implement periodic boundary conditions. Is there a
>> way to do this in gmsh?
>>
>> Note that there will be other stuff in the interior of the cube, e.g.
>> a cylinder, that will also need to be meshed. I know how to create a
>> mesh such that the cube and the cylinder which runs through it is
>> meshed, but I dont know how to create periodic (or similar) surface
>> meshes at opposite faces of the cube.
>>
>> Thanks,
>> -Jehanzeb
>>
>> _______________________________________________
>> gmsh mailing list
>> gmsh at geuz.org
>> http://www.geuz.org/mailman/listinfo/gmsh
>>
>>
>>
>
> --
> Dr. Ir. Ruth V. Sabariego
> University of Liege, Dept. of Electrical Engineering&  Computer Science,
> Applied&  Computational Electromagnetics (ACE),
> phone: +32-4-3663737 - fax: +32-4-3662910 - http://ace.montefiore.ulg.ac.be/
>
>
> _______________________________________________
> gmsh mailing list
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>

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