I am simulating a rapidly rotating (horizontal axis, if that makes a difference) flywheel. The software isn't too sophisticated w.r.t. wind resistance, unfortunately, and seems to use the diameter of the rotating body as one of the main parameters, in addition to the velocity of the rotating body. Consequently, I get pretty much the same results for a rotating disk with diameter (D) and velocity (v) as I do for my rotating flywheel with the same overall diameter and velocity. Intuitively, the rotating thin-walled and narrow cylinder-shaped flywheel, with its lesser surface area, would be less effected by wind resistance than a solid disk of the same thickness and diameter, right? Unless there are odd turbulence effects with the cylinder shape that come into play; anyone know? Anyway, the equation used in the software is F= -D[a(v) + b(v^2)], where a and b are the only values I can modify in that equation. Also, I can totally turn off wind resistance, but that seems to give pretty unrealistic results, and can vary the wind speed and angle w.r.t. the rotating object, although in my case, I have left these 0 to simplify things (I am not sure how these are factored in, exactly, for fixed position objects, especially round, rotating ones). Anyway, anyone have any ideas on what I should set a and b to in F= -D[a(v) + b(v^2)] for my flywheel, or have knowledge of how wind resistance affects this sort of rotating shape? Thanks.