k-epsilon & temperature?

RP

I am trying to simulate temperature stratification for a reservoir with the k-epsilson model using Fluent 6. My model does work for homogenous temp conditions, however when i alter my model for temperture variation the model does not coverge.

Here is my current set-up: -2 velocity inlets with a temperature gradient -1 outlet -no heat flux at reservoir sides -specified temperature at reservoir top -my initial condition is a stratifed temperature

I have the viscous heating turned on and the full buoyancy effects turned off.

I have not implemented a UFD for the turbulent viscosity in terms of temperature, I'm not sure how important this is.

I have set up a Bousinesq density/temperature relationship.

I have tried using the standard wall function and the thermal enhanced wall function.

Any advice?