Simplified engine simulation
 

Hi all;
I'd like to simulate a simplified engine, ie just a nacelle, an inlet and an outlet. Both of the latter will be simple surfaces so the inside of the engine will not be simulated.

Now, the exit area can be a velocity inlet but what abut the inlet area? If I set it as a velocity inlet with the flow going as the flow field (so, pointing towards the engine) I get really strange results, something quite like if the simulation had blown up even though it hasn't…

So, how should I set the engine inlet?

Thank you!

I did not gave enough information: my engine is a jet engine, maybe that's not clear from the title so I would be thankful to a moderator if he/she could edit the tile of this thread.

Anyway I think I solved my problem by setting this condition for the pressure for the inlet: