Issue in the Near wake model of Porté-Agel

[AndiTUM]

Hello everyone,

While comparing your model with the FLORIS implementation we did in TUM, I noticed that the potential core area in the near wake modeled in our implementation deviates from yours.
It seems that you use the rotor diameter for the calculation of the initial wake standard deviation ellipse ellipseA in self_similar_gaussian_velocity.m line 43:
obj.ellipseA = inv(obj.C*turbine.turbineType.rotorRadius.^2);

In the paper (Bastankhah & Porté-Agel, 2016, p.530) a initial wake expansion at x=0 with the vertical major axis dsqrt(u_R/u_0) and the lateral minor axis dcos(gamma)*sqrt(u_R/u_0) is described with u_R being the wind speed at the rotor and u_0 the wind speed inmediately after the rotor when the pressure returns to atmospheric pressure.

I cant find where you calculate u_R/u_0. Is this a deliberate deviation from the paper? If not it could be added to line 43 as I see it.

Best regards,
Andi