I am currently using SOWFA to study tidal turbine wakes and, while trying to calibrate my model, I stumbled upon a problem with the HubRad scalar.
Basically, I have a hub radius of 0.046 m and a blade tip radius of 0.35 m so I expect the body force to go from 0.046 m to 0.35 m along the “fake” radius of the blade.
However, when I look at the velocity on the plane where the body forces are injected, I see that the velocity is only decreased from approximately twice the hub radius.
I tried to play around the values of the hub and tip radius but I did not manage to fix this problem.
However, I looked into the code and I found something which seemed peculiar to me in the horizontalAxisWindTurbinesALM.C: (between line 554 and 580)
This routine computes the actuator center points along the “fake” blade. I do not understand why the x and z components of the bladePoints vector gets twice the “HubRad” value. Indeed, HubRad is contained into root.x() ( respectively root.z() ) as well as in dist.
Hence, if I understood correctly, the body forces would not be injected between HubRad and TipRad but rather between 2 HubRad and TipRad+HubRad, which seems wrong to me.
I am not sure of my understanding of the code, thus I would like to know your input about it.
Thanks in advance,