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Raymond.Leoi February 25, 2013 05:22

C_UDSI_G problem
 
5 Attachment(s)
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?

Amir February 25, 2013 16:47

Quote:

Originally Posted by Raymond.Leoi (Post 409886)
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,

Raymond.Leoi February 26, 2013 12:47

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?


Quote:

Originally Posted by Amir (Post 410023)
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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