Evaporation chamber of absorption refrigerator

Hi there.
Im currently trying to set up a model of an evaporation chamber of an absorption refrigerator.
There is a pipe leading water into the chamber at vacuum(around 50 mbar) and at temp 30 degC. The flow is turbuelent. Inside the chamber the pressure drops to around 10 mbar. Inside the chamber is an external cooling line, a copper pipe with water inside at 5.5 bar and temp around 10 degC, also turbulent flow. At the outlet of the chamber there should be steam(this is not of importanse as it is the chamber im looking into). Anyways, my problem is that i cant figure out which modules i need to use to set up a propper simulation. I am thinking of turbulent flow K-epsilon for the pipe that flows into the chamber, and the same for the flow in the copper pipe. I guess i need some heat transfer module to ad to the copper pipes, and something to model the evaporation of the water in the chamber due to the pressure/temp difference, but I cant figure it out. Also I saw something about a module that can ad a boundary condition that simulates a vacuum pump, and is this needed?
If anyone have some ideas pls let me now :)