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why different results on same model with cosmosflo 07 and flow simulation09?

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Old   May 24, 2009, 22:32
Default why different results on same model with cosmosflo 07 and flow simulation09?
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qihongming
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Same model on cosmosfloworks 2007 and flow simulation 2009 produce different results? please see attachment, this is simple model.

Results:
cosmosfloworks 2007:
Results---surface parameter(Select elements)---click Evaluate-Tab local----Temperature (Fluid) maximum is 59.0421C

However the results of flow simulation 2009 is 77.7825C

I'd appreciated if you can tell me the reasons?

Attachment have exceed 100K, could you tell me howto attach my files?
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Old   May 25, 2009, 20:24
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Glenn Horrocks
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Hi,

There is no attachment so I can't be specific but if any CFD analysis has not been adequately show to have mesh independance, adequate convergence and small enough timestep (if transient) then the result of the analysis is nothing but a random number. Comparisons between different random numbers are pretty pointless.

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Old   May 26, 2009, 01:14
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Thank you very much.
Please see following attachment.
Attached Files
File Type: zip 0525test.zip (69.3 KB, 4 views)
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Old   May 26, 2009, 01:30
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Glenn Horrocks
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Hi,

This is a CFX forum. You won't find many people with Cosmosworks here. I cannot view the file and would not have the time to do a detailed analysis of your simulation if I could open it.

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