Thermal Stratification
 

Hi !

I'm a trainee and i need to study the thermal stratification inside a volume full of air. It's an helicopter cockpit.
So I have to use gravity function in Fluent
I choose incompressible ideal gas for air, and sutherland viscosity
I prescribed 0.039kg/s-340K of air at the entrance (a pipe), then it goes into the cockpit, and then through a pressure outlet with ambiant temperature -293K
I use energy equation, k-e realizable model, Coupled and Presto for pressure and 2nd order for the rest


but I can't see any thermal stratification in the results
Can you help me ?

Did you remember to enable gravity?

The outlet temperature is inconsequential unless there is backflow.

What are your thermal boundary conditions? These are very important because you have an inflow at uniform inlet temperature. Thermal stratification will not occur unless there is some heat transfer that produces a temperature gradient.

Yes gravity is enabled.

My boundary conditions are mass flow inlet with 0.039kg/s-340K and a pressure outlet at 293K
the other are simply wall, adiabatic and convection

Check your thermal boundary conditions.

Remember, if there's no heat transfer, you don't produce any thermal gradients with a uniform inflow, then there won't be an thermal stratification.