[sheldon2020]

Hello,
Im pretty new to this site.I hope im in the right section posting this query.
To begin with, Im working on a CFD project in my university . However im having troubles working around it. I had worked on CFD 2-3 years back and im not an expert on it. Im trying to learn it but im still not sure how to get the required things.
Description : It is an underwater nuclear reactor (2d version) .
The reactor has a PWR core and a heat exchanger embedded in it at the top. The core is operating at a temperature of 250 deg and producing power of 200 MW. Due to this heat produced , the coolant (preferably water ) moves upwards due to a decrease in density and exchanges heat with the heat exchanger at the top and condenses. The heat exchanger is operating at a power of 200 MW and inlet temperature of 60 deg and outlet temp of 90 deg. After the heated vapor condenses down to liquid, it moves out of the reactor into the surrounding pool and naturally circulates downwards towards the higher density region of the liquid that is at the bottom . (I need to capture this natural circulation process that takes place). The pool that is present outside the reactor is at an operating temperature of 70 deg. Ive not mentioned the dimensions of the reactor and other components here , because i just want to know how should i proceed with working on this project. I have done the geometry and meshing and im having trouble with calculations and the fluent part. I just want anyone to please guide me on how should i model the objects (inlet, outlet) or point out if i have done any mistakes (which i obviously have according to me since i dont have much knowledge on CFD).