Hi,

I am implementing Reynolds Stress model for 2D axi-symmetric flows without swirl. Hence I am solving only for UU,VV and UV stresses.

I am facing difficulties in getting a physically realistic solution. When I refer to FLUENT's way of solving 2D axisymmetric flows without swirl, I find that it solves WW stress as well!!! ..How is it possible to have finite WW stress when there is no W velocity component in the first place? Thanks, -Murthy

You forget an important idea: Turbulence is a 3D phenomena.

RSM is a RANS model, which divides the flow into mean flow (U, V, W) and turbulent fluctuations (U*, V*, W*).

You can simulate a 2D axi-symmetric flow with U, V and a mean W equal to 0. BUT THIS DOESN'T MEAN THAT THERE ARE NO FLUCTUATIONS IN THE THETA DIRECTION (WW stress).

SO what you got is realistic.

Hi Kharicha,

Thanks for providing that insight. It really helps!

-Murthy

Because turbulence is a 3d phenomen.

thomas