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unstructured grid wall cells algorithm

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Old   September 9, 2015, 04:42
Default unstructured grid wall cells algorithm
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Shah
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How do we find whether a cell is located at the wall. How would the algorithm do it ?

Thanks in advance


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Old   September 9, 2015, 09:53
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How do we find whether a cell is located at the wall. How would the algorithm do it ?

Thanks in advance

shah
If you are talking about an unstructured code like FLUENT or OpenFOAM, to touch all of the cells adjointing a wall boundary, you loop over the faces in the wall thread/patch and look up the cell connected to each face (F_C0() in FLUENT, etc).
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Old   September 10, 2015, 07:09
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Thank you for your reply.
In fact I am programing it using fortran. Plus I am using unstructured mesh. I am curious how would a triangular cell with only one of its vertices located on the wall effect the algorithm.
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Old   September 10, 2015, 08:00
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How do we find whether a cell is located at the wall. How would the algorithm do it ?

Thanks in advance


shah
Quote:
Originally Posted by researcher View Post
Thank you for your reply.
In fact I am programing it using fortran. Plus I am using unstructured mesh. I am curious how would a triangular cell with only one of its vertices located on the wall effect the algorithm.
Thanks
It won't. If you are using FVM, the entire scheme is based on surface integrals over each cell. A single vertex has no area to integrate over, so its contribution is zero. Only finite area faces will contribute to the flux balances that you write for each cell.
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Old   September 10, 2015, 10:06
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It won't. If you are using FVM, the entire scheme is based on surface integrals over each cell. A single vertex has no area to integrate over, so its contribution is zero. Only finite area faces will contribute to the flux balances that you write for each cell.
Haha, of course. Thank you. Your reply made both my work and the day.
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