Conjugate heat transfer defining fan velocity INSIDE flow region

Hello everyone,

I am trying to define the air pressure exerted by a fan that is inside a flow region (not on an flow region boundary) similar to how a fan inside a laptop is not applying pressure to the flow region at the air inlet or outlet but somewhere inbetween. Is there any way to do this/ examples?

I was first thinking of a momentum source but for that you define the velocity instead of pressure.

Alternatively, have a look at this post: Custom BC: Fan pressure