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 Kinng November 12, 2019 19:54

Hovering rotor thrust coeff values

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Hi,

I have been trying to simulate a hovering rotor case of Caradonna and tung.

I used overset mesh to prescribe rotation (Rigid body rotation) to the rotor blades.

I have obtained thrust coeff value for the case and it is 100% greater than the experimental value. I have even obtained mesh convergence results and have been using a time step of 1 degree rotation.

If anything rings a bell please let me know. I believe I am using right setup as following literature but not sure where its going wrong.

Just to clarify: collective pitch angle of 8 degree means each rotor blade has a pitch angle of 8 degree right ?

Thanks

 dmirel November 13, 2019 02:28

Hello,

I am working for a while at a VAWT concept and I used the same procedure with overset mesh and DFBI and works well.
I did validated my simulation results with experimental data.

Pay attention that the maximum rotation allowed in one time-step should be max of the smallest cell size from the overset mesh, not 1 degree of rotation.

In the beginning I had problems with with the power output because of the DFBI inertia moments, my input was wrong. I calculated them again and the results improved.

Good day,
dmirel

 cwl November 13, 2019 06:59

Quote:
 Originally Posted by dmirel (Post 749627) Hello, I am working for a while at a VAWT concept and I used the same procedure with overset mesh and DFBI and works well.
Why wouldn't Region with Rotation Motion be sufficient for modelling VAWT?

 dmirel November 14, 2019 11:05

Cwl,

For some people is enough, for others is not but I did not said that is not enough :)

dmirel

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