Reynolds number for 0.4m chord length and 75m/s (270kph) = 2.1 x 10.6 --> Critical AoA = 15 degreestimbo wrote: ↑Tue May 14, 2019 7:20 pmThe graph covers many orders of magnitude difference in Re number, this is much much higher than the changes dut to velocity difference between t9 and t10. Also, on the graph, you'd see a highly nonlinear behavior of the Cy/Cx curve, and between some Re number values, the position of maximum may increase or decrease.DRCorsa wrote: ↑Tue May 14, 2019 1:27 pmReynolds number is a function of airspeed.
Critical AoA is affected by the separation of the boundary layer, which is a directly dependent on Reynolds number.
Take a look at the following graph. You will see that for higher Reynolds numbers, critical AoA is higher too.
That's the reason why SF90's front wing won't stall at high speeds, but will stall at low speeds.
Anyway, the effect of the pitch attitude of the car is more important here.
Reynolds number for 0.4m chord length and 28m/s (100kph) = 7.8 x 10.5 --> Critical AoA = 12 degrees