A new wake model for annular devices
It occurs to me that a better design for wake steering optimization is to construct the wind farm with towers of varying heights. Cosine cubed losses for angles of 10, 15 and 20 degrees, are 4.5%, 9.9% and 17.0% respectively. In contrast if we lower the tower height from 60 meters to 50 and 40 meters, power output will be reduced by 1.21 and 2.42% respectively. If we raise the tower height from 60 meters to 70 and 80 meters, power output will be increased by 1.22 and 2.46% respectively. These numbers are empirical, and may vary a lot, but the overall conclusion is that power loss from a skew angle is much more than varying tower height. Unfortunately, tower heights must be established in the design stage.
Any interesting conclusions or new data ?
Here are my thoughts. We know that wind velocity gradients on the ocean are less than on land because there are no ground obstacles to create turbulence. So, varying the height of the turbines on the ocean will cause minimal losses. This might be easy to do with floating turbines by varying the amount of ballast. On the other hand, turbines can be spaced further apart in the ocean at little additional cost.
As far as I can tell, it proves that the doughnut shape degrades into just dough maybe more porridge or ice-cream like depending on the doughnut