SimScale CAE Forum

Inlet and Outlet not working for actuator disk?


#1

I am trying to model a prop as an actuator/momentum disk. I have tried the momentum source option but couldn’t get it to work so instead have a mass flow inlet and outlet over a disk which seems to be working fine. However, my boundary inlet and outlet when set to a velocity inlet and pressure outlet causes the flow to travel at 10,000s m/s which is ridiculous. In addition, when I set both to velocity inlet/outlet I get flow values of 10s m/s which is realistic for the prop I am simulating but. The flow never travels through the boundary it just recirculates as if the inlet and outlet are walls.

In addition I can’t seem to get flow lines to work either so I can also see what is going on by using a vector field which isn’t great either :confused:.

Any help with any of these problems would be massively appreciated.

https://www.simscale.com/projects/ethbond_drones/actuator_disk_v2/


#2

@CFD-SQUAD, can you help out here? :slight_smile:

My point of view: Momentum Source is missing if you want to make it an actuator disk, also I would not prescribe the mass flow rate for both faces, maybe try the following:

  • Inlet: Custom BC with velocity as a mass flow rate
  • Outlet: Depending on the physics of your problem pressure defined as gauge pressure

Maybe the PowerUsers can add another setup option which would make more sense here.


Cheers,

Jousef