[zhenduan306]

Hi, Dear friends,
I am simulating HAWT now. My purpose is to obtain the curve between shaft power and RMP(or wind speed , TSR).

I used the way ghorrocks mentioned in
http://www.cfd-online.com/Forums/cfx...on-baldes.html

"Far easier, but a little less elegant is to sweep through a range of rotation speeds in a series of steady state runs. This will give you a torque/power versus speed curve. Then interpolate on this curve your intended torque/power and there you have it. If you like then run this point as well to improve the accuracy of the interpolation"

The weird thing is, when I fixed wind velocity, I increased rotational speed and torque increase too. The result is Cp is more than 0.59 (betz limit).
For example, wind speed=8m/s, angular velocity are 20 rad/s, 40 rad/s and 50 rad/s, respectively. The corresponding torque are 8.5, 22.35, 34.8 N.m. I think it is wrong. Because when wind speed is constant, the total wind power in the rot domain of the blades is fixed. Higher rotating speed means lower torque.



(my analysis type:steady)

Hence, I want to add CEL to my cfx-pre. This link gives me some clues:
http://www.cfd-online.com/Forums/cfx...imulation.html
from his CEL: he defined wind power as an expression. But I don't understand where he used it.

in my mind, I think the wind power and Betz limit should be as the constraint conditions. Otherwise, the results will be wrong.

These are my CFX pictures:



Any help would be greatly appreciated.