[hiraku]

Hello,

I am new to OpenFOAM and have been wondering how to model a ducted fan in hover. If anyone could advise me on how to model it, I am grateful.

At this moment, I would like to keep it simple without having to use a moving mesh and just use a in/outlet perhaps?


Regards,

hiraku

[gdbaldw]

I'd start with a torus having an inlet and outlet patch at the hole in the middle. On the inlet fix the velocity, and on the outlet fix the static presure to an appropriate value for the inlet velocity. I'd initially make a single far-field patch with a constant pressure. After that works, you could properly shape the duct and add inlet/outlet at the far-field to represent wind.

Doug

[gdbaldw]

Clarification...duct inlet (which is an outlet of the computational domain) has constant pressure, and duct outlet (which is an inlet to the computational domain) has constant velocity.

[hiraku]

Thank you for your advice.

I have created a torus with surface in the middle of the hole using SALOME. The torus is contained in a larger cube. This was meshed and exported as .unv Then I used ideasUnvToFoam to convert the file for OpenFOAM. I wasn't so sure which solver to used so, decide to use icoFoam since it doesnt require alot of set up. Unfortunately, the results do not make sense; with velocity and pressure running random.

The boundaries of the cube and the torus are set as "wall". The inlet and outlets are set as you have advised; torus outlet as "inlet" and torus inlet as "outlet". The rest of the parameters are the default of the tutorial contained in icoFoam with the exception of pressure (1e5 Pa) and all of controlDict.

I do not know what the problem could be. I feel that the meshes maybe too large or that the I have set something incorrectly.

Currently, I am trying to use a finner mesh. Any advice is appreciated.


Regards,

hiraku