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Old   December 3, 2011, 17:43
Default Help on judging imbalance plots
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Hello,

I could use some help on judging the imbalance plot in CFX solver module. Unfortunately I could not find much information about this in the help texts. The P-Mass Imbalance in this plot is jumping randomly from -100 to 100, where as the other imbalances seem to stay at zero. I'm wondering how to inteterpret this and if it has got something to with the other residuals. The boundary is a sphere, set to opening, entrainment, static pressure option.

Thank you very much for your help.

Stefan
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File Type: jpg residuals.JPG (84.2 KB, 18 views)
File Type: jpg turbulence.JPG (71.2 KB, 18 views)
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Old   December 4, 2011, 05:38
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The imbalances are calculated with a divisor of the total flow through the domain (I think, please correct me if I am wrong). If the domain has no entrances or exits so has no net flow, then small imbalances from the continuity equation cause the result to flip from +lots to -lots. It is meaningless in this case, so ignore it.
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Old   December 4, 2011, 08:34
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Thank you Glenn, that helps.
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