[vd93]

Hi,

I am rather a beginner in OpenFoam, so please do excuse me if this question sounds a bit too trivial.

I am currently working on the CFD analysis of a Horizontal axis wind turbine using OpenFOAM for my master thesis. I am running a clean blade for a free stream velocity of 8m/s and omega 36.577 rad/s. I have got the results and they do seem reasonable based on the pressure distributions over the blade as well as the flowfield around the blade.
I have successfully calculated the power coeffcient for my blade and am getting an error of 5% when compared to the experimental case.

As for the thrust coefficient, I am getting an error of about 16% compared to the experimental results.

I believe I am making a mistake in regards to the thrust force calculation from the log file. Presently, I am calculating the thrust by obtaining the average of the pressure and viscous forces along the direction of the flow (y axis in my case) for the final 1000 iterations and implementing the following formulae.

Thrust_force = (pressure_force_avg * density) + (viscous_force_avg);

and consequently the Ct as,

Ct = (Thrust_force)/(0.5 * density * V^2 * Area);

I would like to know if my above calculation is correct or not and if not a correct solution would be much appreciated.

Thank you for your time!

-Varun

[muhammss]

Did you manage to get the correct answer?
How did you calculated the Cp? I mean the formula?

[CFD-Shiraz]

Originally Posted by vd93

Hi,

I am rather a beginner in OpenFoam, so please do excuse me if this question sounds a bit too trivial.

I am currently working on the CFD analysis of a Horizontal axis wind turbine using OpenFOAM for my master thesis. I am running a clean blade for a free stream velocity of 8m/s and omega 36.577 rad/s. I have got the results and they do seem reasonable based on the pressure distributions over the blade as well as the flowfield around the blade.
I have successfully calculated the power coeffcient for my blade and am getting an error of 5% when compared to the experimental case.

As for the thrust coefficient, I am getting an error of about 16% compared to the experimental results.

I believe I am making a mistake in regards to the thrust force calculation from the log file. Presently, I am calculating the thrust by obtaining the average of the pressure and viscous forces along the direction of the flow (y axis in my case) for the final 1000 iterations and implementing the following formulae.

Thrust_force = (pressure_force_avg * density) + (viscous_force_avg);

and consequently the Ct as,

Ct = (Thrust_force)/(0.5 * density * V^2 * Area);

I would like to know if my above calculation is correct or not and if not a correct solution would be much appreciated.

Thank you for your time!

-Varun

Hello,

I have the similar problem. What is velocity and area? How did you calculate the area.?