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Twix June 24, 2009 09:30

Different temperature on boundary fluid-solid in CFX
 
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Hi,
I have problem and need help. I do CHT simulation of flow around turbine vane and use SST
model with and without turbulence transition and K-Omega model. I create line on boundary
fluid-solid and check temperature. The temperature on
solid side is different from this on fluid side. The difference is about 5%. My question is
why, because those value suppose to be equal. I add chats.
Thanks in advance

ghorrocks June 24, 2009 18:49

Hi,

For CHT simulations you should add imbalances as a convergence critereon in addition to the normal residuals. What imbalances have you converged to?

Glenn Horrocks

Twix June 25, 2009 16:11

Hi,
thanks for so fast reply. my settings for convergence criteria are: Residual type- MAX, Residual target- 0,00001. In expert parameters I didn’t mark imbalance normalization type.

Regards

ghorrocks June 25, 2009 18:50

Hi,

As I said, a CHT simulation can have high imbalances (which leads to temperature imbalances) but well converged residuals. That is why you should also use imbalances as a convergence critereon for CHT simulations. It is on the solver tab in CFX-Pre (not an expert parameter).

Glenn Horrocks


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