Huge Heat Transfer Coefficient with SST turbulence model
 

Hello!

I am modelling conjugate heat transfer at a pipe - the pipe is cooled by air, which flows through the pipe. Therefor I use the SST turbulence model. The y+ value is y+ <1 (around 0.5) The number of nodes in the boundary layer is about 15. The value for the wall heat transfer coefficient which i got from the simulation is very high with 26105,7 W/m²K (From analytical calculations I got a value around 650 W/m²K)

Does someone know what the reason could be?

Thank you in advance,
Andy

try to check reference temperature for calculation of HTC

The temperatures are ok. I did the simulation also with the k epsilon turbulence model (with scaleable wall functions) and then I got much better results than with the sst model. So I dont understand why the results with use of the sst turbulence modell are so high.

I don't think you have understood denizen's point. HTC is by default referenced to a local temperature which is another variable available for viewing in CFD-Post called "Wall Adjacent Temperature". This variable is often miles away from the reference temperature an engineer would use in the bulk flow.

Thank you! This was very helpful!