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Dead cell causes singularity?

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Old   September 28, 2011, 12:44
Default Dead cell causes singularity?
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liu
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Xiaofeng Liu
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I have a mesh where there is a cell which is totally surrounded by walls, i.e., it is a "dead" cell. This cell is isolated from others.

When I do icoFoam, it exited with a segment fault.

So what could be the problem? Does this cause singularity? Or the status of the system is undetermined?

One thing I might do is to delete these "dead" cells from the mesh since they don't contribute to anything. But how can I do that?

Thanks.
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Old   October 1, 2011, 15:38
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Bruno Santos
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Greetings Xiaofeng Liu,

Check this tutorial: http://openfoamwiki.net/index.php/SetSet
You can use those instructions as a reference to the steps you need to do:
  • Run checkMesh to create the cellSets for the list of damaged cells;
  • Then use setSet to select said cellSets, then invert selection to select the good part of the mesh;
  • Then use subsetMesh for saving only the good part of the mesh.
Good luck!
Bruno

Last edited by wyldckat; October 14, 2011 at 17:21.
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Old   October 14, 2011, 10:28
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liu
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Thanks for the reply, though you answer is not relevant.

I have figured out this. For the record, it seems that those dead cells has no effect on the solution at all. They are not participating in the calculation since no flux could pass through the surrounding walls.

You might be able to subSet these cells out but again it is not necessary.
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Old   October 14, 2011, 17:23
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Hi Liu,

Well, I can't always be right But still, I did (sort-of) answer your last question on the initial post:
Quote:
Originally Posted by liu View Post
One thing I might do is to delete these "dead" cells from the mesh since they don't contribute to anything. But how can I do that?
But I'm glad you figured it out by yourself

Best regards,
Bruno
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