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Old   July 12, 2011, 10:38
Default Help~!! undefined cells
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Dijun Pan
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Dear all friends

I defined a smooth free surface using mesh that matches the initial wave profile,and then remeshed to hex mesh it after a few step. But when I check the volume fraction of XZ plane face, there are many undefined cells and the remeshed mesh was broken. But when I check the mid face, the cell is smooth.. Why this happen!? Is it because geometry problem??



Thanks a lot

Dijun
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File Type: jpg undefined mesh@0s.jpg (25.6 KB, 12 views)
File Type: jpg undefined cell after remeshing .jpg (79.0 KB, 10 views)
File Type: jpg undefined cell after remesh_2.jpg (54.8 KB, 9 views)
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Old   July 12, 2011, 18:55
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Glenn Horrocks
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Why are you remeshing? This model should work fine without remeshing.
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Old   July 13, 2011, 09:33
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Dijun Pan
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Quote:
Originally Posted by ghorrocks View Post
Why are you remeshing? This model should work fine without remeshing.
Thank you. In order to create a smooth wave profile I use the mesh to match the profile which does not has uniform cell, I thought better results can be obtained by remeshed to the structured mesh, but it seems does not work.
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Old   July 13, 2011, 19:36
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Glenn Horrocks
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I would think you remeshing is going to do more harm than good. You should be able to use a very high quality hex grid on this simulation and free surface models work very well on high quality meshes. Your remeshing is significantly reducing the mesh quality. A step backwards in my view.
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Old   July 14, 2011, 09:08
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Dijun Pan
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Quote:
Originally Posted by ghorrocks View Post
I would think you remeshing is going to do more harm than good. You should be able to use a very high quality hex grid on this simulation and free surface models work very well on high quality meshes. Your remeshing is significantly reducing the mesh quality. A step backwards in my view.
Thank you so much for the advices!! I will do several more trial and if it does not work I ll not use remesh.
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