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CT and CTy value calculation
I was doing a HAWT simulation for various yaw angles[0,5,10,15,20,25] and various tip speed ratios[4,5,6,7,8]. The simulation run time was for 0.1 second. I did get the CT value for each simulations. The problem is that the documentation of Qblade says CT = 4a(1-a) where a is the axial induction. If I try to find the value of a, there are 3 blades each with PAN 0-19, therefore I cannot find it.
I also tried using the formula, CT=8*Thrust/(pi*air_desnity *wind_speed^2 *rotor_dia^2). This formula gave me the value for CT almost similar to that of simulation result. But in case of yaw 20 and 25, the value are not close as before.
I used the thrust force by taking its average in the last revolution.
My ultimate goal is to calculate the CTy ( cross- stream thrust component). I was thinking if I can use the same CTy=8*Thrust_in hub_y_direction/(pi*air_desnity *wind_speed^2 *rotor_dia^2). But since this formula did not work in case of CT, I wonder if it will work in case of CTy also.
