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Zerit June 10, 2013 04:23

Cell definition diffrence
 
Hello All,

After running a simple model of water flow in an open canal. I get a part of the domain a little bit bigger than the neighbouring region. Eventhough the canal is straight I see a step in one specific area. Actually this area is defined by a smaller mesh size. Is there any difrence in the definition of a given cell in the preprocessing and post processing (cell defined by its center or by the edges)?

I appreciate your comments in advance.

Regards,

MuxaB June 12, 2013 08:41

Quote:

Originally Posted by Zerit (Post 433032)
Hello All,

After running a simple model of water flow in an open canal. I get a part of the domain a little bit bigger than the neighbouring region. Eventhough the canal is straight I see a step in one specific area. Actually this area is defined by a smaller mesh size. Is there any difrence in the definition of a given cell in the preprocessing and post processing (cell defined by its center or by the edges)?

I appreciate your comments in advance.

Regards,

No, it should be the same. Are you using multiple mesh blocks with different resolutions? If so, the pre-processor may show a small gap between them (or a change in cross-section), but it is most likely a plotting glitch rather than a real problems.

The pre-processor reports the differences in open areas at adjacent block boundaries. Look in prpout file, search for 'information' to see the actual numbers.

Zerit June 12, 2013 16:48

Thank you MuxaB.

Yes I am using multiple mesh blockes and I clearly understand your point. The trend of the selected paramter as well as the values don't get changed only the gap is the problem.

MuxaB July 13, 2013 14:31

Then it is most likely a plotting artifact.



Quote:

Originally Posted by Zerit (Post 433665)
Thank you MuxaB.

Yes I am using multiple mesh blockes and I clearly understand your point. The trend of the selected paramter as well as the values don't get changed only the gap is the problem.


Zerit July 14, 2013 12:58

it is basically a problem related with the nested mesh block definition. with better transition and mesh plane at the ends of the nested mesh block this problem was sorted out. In fact it helped me in detecting any problems in the mesh definition.

Zerit July 14, 2013 14:25

i don't think it has anything to do with the plotting.

MuxaB July 14, 2013 17:55

Glad you figured it out. Nice work!


Quote:

Originally Posted by Zerit (Post 439655)
it is basically a problem related with the nested mesh block definition. with better transition and mesh plane at the ends of the nested mesh block this problem was sorted out. In fact it helped me in detecting any problems in the mesh definition.



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