3DEXPERIENCE - How to define multiple fluids within same FMK model?

Hello everybody,

I need to create FMK model of Chimney and to simulate flue gas (water vapor) behavior where wind velocity is very high.
Please find attached picture bellow.

Input data includes chimney volume flow rate, flue gas temperature, wing velocity, atmospheric pressure...

Can someone with experience in this kind of simulation help me by giving some instructions how to create two different fluids within the same FMK model?
Are there any specifics which should be defined in order to simulate multiple fluids and predict their behavior?

Thank you.

3DEXPERIENCE FMK