In flight mechanics, “constant torque” refers to a condition where the engine or propulsion system of an aircraft generates a constant level of torque output, regardless of the engine’s rotational speed (RPM). Torque is a measure of the twisting force produced by the engine’s crankshaft and transmitted to the propeller or rotor system.
Q0 = P0 / (2 * π * n0)
Q0 = Volumetric flow rate of air through the compressor or fan (typically in cubic meters per second or cubic feet per minute). P0 = Power input to the compressor or fan (typically in watts or horsepower). n0 = Rotational speed of the compressor or fan (in revolutions per unit of time).