Ramjet Intake Simulation
 

Hi all,

I am trying to simulate (Inviscid FLow) a Ramjet Intake. Please find the geometry and BC in the attached figure.

I used the following BC

1. Inlet - Pressure Inlet
2. Freestream - Pressure Farfield
3. symmetry - axis
4. wall - slip
5. outlet - Pressure Outlet

I specified pressure at the outlet to get a normal shock in the constant area portion of the intake.

First i initialized with fully supersonic flow and specified static pressure at the outlet, but the outlet BC was not sensed, which the simulation resulted in fully supersonic flow.

So i initialized with fully subsonic flow and specified static pressure at the outlet, but the flow reversal at the outlet and the solution is not converging.

So what would be a good strategy to simulate this kind of problem in fluent.

you should'nt specify a far field in such close proximity to your region of interest, well that true of most Bc's. Remember at a BC your are fixing values and if this is close to large gradients then you specify one side of that field.

If you want to model a nacelle with a ramjet inside then if this were to be 3 metres long for example the far field should be a half elipse shape, nominally 60m in diameter.

create the free stream boundary in front and extend the outlet boundary.