Working with topology

Hello every body

I face some problems by exporting an .IGES file wich includes a topography shape.

How do I proceed to create correct boundaries that works for bolean operations and for meshing.

Exemple of one problem I met : I export my .iges and then build a shell from it. I repair the shell (sewing etc...) and built a solid. I would like to perfom some bolean operation to it but it always lead to incorrect shapes, and when it work, two faces desapear, the topography face and a side face resulting to impossible repair.

thanks for you help.

importing of course sorry

Previously Bonan wrote:

Hello every body

I face some problems by exporting an .IGES file wich includes a topography shape.

How do I proceed to create correct boundaries that works for bolean operations and for meshing.

Exemple of one problem I met : I export my .iges and then build a shell from it. I repair the shell (sewing etc...) and built a solid. I would like to perfom some bolean operation to it but it always lead to incorrect shapes, and when it work, two faces desapear, the topography face and a side face resulting to impossible repair.

thanks for you help.

 

Hello, Bonan,

Maybe you could enclose the shape to import and a dump of your study (with [Ctrl] + [D]). Because it seems that your method is good.

William

Thank you for your help William

I abondonned the idea to perform boleans on my solid. I am trying now to use the body fitting to mesh my untruncated solid. I create a python script usind coordinates and now I am facing a new problem : In trying several configurations it always lead to this kind of error message : 

Cartesian_3D failed on subshape #1 with error COMPERR_ALGO_FAILED "Wrong END (or SOLE) transition of GridLine (...,...) along whatever X,Y or Z: IN

Do you have a method to fix the problem efficiently ?

Thanks for your help

Hello Cyril Bonan

If you attached (or transfered any other way) your model, your case could be analyzed to see if it is a bug of algorithm.
Meanwhile you can try to decrease tolerance of your model (menu Repare / Limit Tolerance).

Best regards

Edward

Hello Edward and thanks to you

I can't post my study...

What is the tolerance about? can you explain me please?

Tolerance is explained in this doc (there is a dedicated chapter) http://docs.salome-platform.org/salome_6_5_0/gui/GEOM/SALOME_BOA_PA.pdf

Varying the tolerance sometimes helps while constructing geometry, and in your case there is a small chance that this could help.

Best regards
Edward

Thank you SMESH expert.

How do I choose my grid to enclose my domain ? should I let large space each side or the closer to the extremity of my domain?

Strictly speaking it does not matter. But if you make your grid larger you have a chance to avoid the mentioned errors by shifting the whole grid (at least every node close to face boundary) a little in direction(s) perpendicular the direction reported by an error message.

Regards
Edward

Edward, can I send you a private message with my domain and scripts ?

Yes, I've  sent you a message to cyril.bonan(AT)gmail.com.

Edward