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ai_agora_e_que_e March 13, 2006 20:02

Boundary face 7
Dear all

When working with trimed cells, without subsurface, we often found a trimmed cell adjacent to the boundary. If the 7th face of that cell is a boundary face, it can not be good...

Question: instead of remeshing, there anybody know the way to deal with it? Can we automatically rotate these cells in order to put the 7th face connected to the bulk cells?


Oliver March 14, 2006 05:57

Re: Boundary face 7
From my understanding trim cell faces 7 and 8 are internally linked to other faces handeled as partial boundaries, so this should not make a problem if these faces are wall boundaries. But on the other hand you are right, you cannot have different boundary conditions on both linked faces. That is why you have sometimes problems with baffles or boundary conditions on certain trim faces

If you want to put other boundaries on these faces, there is no automatic method to 'rotate' the cells. There is a command cmrefine, which refines trimmed cells into regular cells with additional couples. On outlet boundries you could extrude one or more layers and put boundary conditions there. And the last possibility is to fix or rotate manually.

Best regards, Oliver

ai_agora_e_que_e March 14, 2006 20:41

Re: Boundary face 7
Many thanks for you answer.


Anton Lyaskin March 15, 2006 03:50

Re: Boundary face 7
Actually this issue is covered in the User Guide (though it's not emphasized :) - in this case you have to extrude at least 2 layers of prisms. If your [former] boundary face has more than 4 corners then you'll have to divide "multi-vertex" prism you get there into "normal" 6-vertex prism and couple them to the initial face. Not sure that it can be done automatically, but probably CMREFINE with proper parameters will do the job.

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