The torque coefficient (CQ) is a dimensionless parameter used in the analysis of propellers and rotors, particularly in aerodynamics and flight mechanics. It represents the efficiency with which a propeller or rotor converts the torque applied to it into the thrust generated. The torque coefficient is crucial in understanding the performance and efficiency of these propulsion systems.
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CQ = Torque coefficient Q = Torque applied to the propeller or rotor (in Newton-meters) ρ = Air density (in kg/m^3) n = Rotational speed of the propeller or rotor (in revolutions per second, RPS) d = Diameter of the propeller or rotor (in meters) C = Blade chord length (in meters)