[Gmsh] How to get two identical meshes on two faces

[Olivier Pierard]

I've to mesh a cube containing several ellipsoids randomly oriented. 
 Since I want to impose periodic boundary conditions, two opposite faces 
of the cube mush have exactily the same mesh.  How can I force it since 
when drawing the basic geometry, meshes of two opposite faces are 
slightly modified by the influence of the ellipsoids.

Thanks for your help,

Olivier

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** Olivier Pierard                                  **
** PhD student, UCL                                 **
** Center for Systems Eng. and Appl. Mech. (CESAME) **
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