Boundary conditions for a 2D ducted fan?
 

I have a ducted fan mounted on a wing. And I don't want to simulate its real geometry. How should I set the boundary conditions.

If it is 3D, I can use the rotor model to simulate the rotor without rotor geometry. And I can see the flow boosting effect across the rotor disk.

But now I want a 2D simulation, is there any boundary condition I can use? like a baffle, the flow will be sucked in when the flow reach the baffle, and the flow will eject out when the flow leave the baffle? The flow will have a total pressure boost across the baffle?

Thanks.