[Tianxu]

Hi everyone,

I am doing 2D rotating detonation engine (RDE) simulation in ANSYS Fluent.

For inlet boundary condition, there are three possible cases:

1. Pi > Po, where Pi is the pressure inside the domain immediately at the inlet and Po is the total inflow pressure. In this case the pressure inside the RDE at this point is very high and blocks inflow of new mixture through the inlet face. The inlet boundary acts as a wall.

2. Pcr < Pi < Po, where Pcr is the critical pressure. In this case the inlet is not chocked and new mixture flows into the RDE according to: mass flow rate = the integral of (rho*u*dA).

3. Pi < Pcr, in this case the pressure inside the domain is low. The inlet at this point is choked, so maximum flow rate of fuel is flowing into the domain. Pcr is calculated from isentropic relation.

I'm not quite sure how to construct UDF for this inlet condition. It would be very appreciate if someone could help me out!!!