[edmondlam]

Hi, I am doing a simulation with FLUENT 14.0 for both boiling and condensation processes in a closed domain.

My system is a cylindrical tank which is heated at its bottom. Water is put inside the tank. There are fins on the outer wall of the cylinder. As the system heats up, water in the tank boils. The water vapor travels to the top of the interior of the tank, and dissipates heat by condensation to the tank wall and then through fins to the surroundings.

My problem is that in FLUENT 14.0, if I enable the RPI boiling model, there is only one mass-transfer mechanism, "boiling", from liquid to vapor available. I cannot add an "evaporation-condensation" mass-transfer mechanism from vapor to liquid in the phase interaction panel. Thus then FLEUNT only models the boiling process but not the condensation process.

Is there a way to implement both RPI boiling and condensation in one simulation without using a UDF

or is there any other better way of doing this

it is kind of frustrating

Thanks in advance!

My geometry only includes the tank + fins (no modelling of flow of surrounding air). I chose "convection" as the boundary conditions for the exterior of the cylinder, and "temperature" as the boundary condition for the part of the cylinder that is heated. It is a conjugate heat transfer problem, I have meshed both the water and the solid (tank wall + fins).