conjugate heat transfer problem

Andreas

Dear CFD users,

I have a conjugate heat transfer problem in a complex internal flow geometry. The analysis procedure I have used is to keep the convection study separated from the conduction study, due to limitations in computational resources, and also due to the fact that mechanical integrity analysis will anyway be performed separately (with a different code) for this problem.

For the post processing of the convection study I have up till now used T_ref = Tbulk = a global temperature, which I know will not work if the fluid heat is entering and exiting the solid at the same time (at different locations) due to negative HTC's. The benefit of this approach is however that the grid dependence of the HTC is eliminated and the solution is roughly independent of the wall boundary condition (I use an "average" constant temperature at the wall). The other way would be to use the approach that is standard in most CFD codes; the near wall node temperature as a reference temperature (T_ref = T_nwn). But then the solution is probably grid dependent and surely strongly dependent on the wall boundary condition (i.e. specified temperature level in my case). What would You prefer?

regards Andreas