flow in tube with heat transfer
 

dear all,

I'm simulating flow in pipe with heat transfer using chtMultiRegionFoam. pipe is 1m long 20cm dia. velocity is 0.1m/s.

could any one suggest suitable cells size and time step for this case because it always diverge.

thanks in advance.
:)

dear ahmad, i think you need to post your setup here, may be there are other issues for divergence ( for example inappropriate BCs, or high order schemes or ........)