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Old   February 25, 2013, 05:22
Default C_UDSI_G problem
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I managed to collect the gradient of a diffusivity through UDS. It's observed that UDS is correct everywhere, but C_UDSI_G is wrong near boundaries even it is no problem within the computional domain. To demonstrate this problem, one simple case with UDF was attached (flntgz4.zip is case file and flntgz5.zip is data file). If you run the case once, you can see the wrong gradient near BC by GUI, which is supposed to be constant 0.021. Anyone can do me a favour and see how to solve it?
Attached Files
File Type: c hsrc.c (968 Bytes, 6 views)
File Type: zip flntgz4.z01.zip (90.0 KB, 5 views)
File Type: zip flntgz4.zip (87.2 KB, 5 views)
File Type: zip flntgz5.z01.zip (90.0 KB, 2 views)
File Type: zip flntgz5.zip (28.8 KB, 1 views)
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Old   February 25, 2013, 16:47
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Quote:
Originally Posted by Raymond.Leoi View Post
I managed to collect the gradient of a diffusivity through UDS. It's observed that UDS is correct everywhere, but C_UDSI_G is wrong near boundaries even it is no problem within the computional domain. To demonstrate this problem, one simple case with UDF was attached (flntgz4.zip is case file and flntgz5.zip is data file). If you run the case once, you can see the wrong gradient near BC by GUI, which is supposed to be constant 0.021. Anyone can do me a favour and see how to solve it?
Hi,

I haven't checked your files but I guess the issue is due to the difference between cell and node values specially if you have large cells near boundaries.

Bests,
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Old   February 26, 2013, 12:47
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Thanks, Amir. Well, even I refine the mesh, the value is still wrong. It is probably because the values at boundaries haven't been specified, since the properties are just assigned to cells. Any further suggestion?


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Originally Posted by Amir View Post
Hi,

I haven't checked your files but I guess the issue is due to the difference between cell and node values specially if you have large cells near boundaries.

Bests,
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