🌾 English Tower Windmill: Sail Pitch, Betz Limit, Gear Train and Millstone Flour Yield Lab

A cut-away Norfolk brick tower mill you can run: set the wind speed and the sail angle, release the brake and watch the sails, brake wheel, wallower, great spur wheel and runner stone turn. Rotor power follows P = 1/2 rho A v^3 Cp(lambda, pitch) under the Betz limit, a 6:1 gear train sets the stone speed, and flour yield comes from grinding energy. Educational model, simplified.