[thepassenger]

Hi,
I am trying to model the fluid around an airplane fuselage, including propeller effects.
I have read that a Fan boundary can be used to simulate a propeller, but am I unsure of how to prepare my geometry and mesh in gambit. I attached a quick sketch of what I am trying to do...
If someone could give me an idea on how to do it, I would be very thankful!

Thank you

[kerhart]

Your geometry sketch shows that you have the correct idea for how to do this. The fan condition is applied to an interior region/face, therefore you should create a face within the fluid flow region (a circular face, since I assume this is a 3D flow problem) at the location where you would like to have the propeller. You have to make sure that when you mesh this face it is part of the overall mesh for the problem (sometimes the face geometry is not connected to the rest of the volume and you will end up with two separate meshes instead of a single mesh with a face partition within it). How to do this depends on what program you are using to create the geometry and mesh; I believe that in Gambit you need to designate this face as a partition. I would also recommend meshing this face first (alone) and then meshing the volume. While meshing the volume watch to make sure that the volume mesh is congruent with the face mesh at this location (this shows you that the face partition has been included correctly).

Once your mesh is ready, just choose the Fan option in Fluent to simulate the propeller as desired. Be sure to double check the direction the fan is flowing as fluent may choose the opposite direction that you need (there is a check box to reverse the flow direction for the fan).

Best of luck to you.

Kevin Erhart
Mechanical Engineer
Central Technological Corporation
www.centecorp.com