[Andytzki]

Hi,

I am dealing with a concentric tubes heat exchanger where the inner tube is an oval twisted tube. The flow on both sides is turning due to the twisted geometry and I am trying to use the best turbulence model to solve the heat transder from one fluid to the other. I tried standard K-epsilon, realizable, and RNG (good for swirl?).

Can someone please point me in the right direction? Realizable K-epsilon gave me a nice converged answer but RNG gave me a different answer.

In case you need this info I am using velocity inlets, pressure outlets, and air as the fluid.

Thanks in advance!

Andrew