Propeller Aerodynamics

This page provides a summary of the aerodynamic properties to be used in the analysis of each propeller's performance.

Thrust Coefficient

Describes the forward force that a propeller exerts on an aircraft. This relationship is given in equation (1) where T is the propeller thrust, rho is freestream density, n is the rate of rotation, and D is the diameter.

Torque Coefficient

Describes the axial twisting force that the propeller produces. This relationship can be seen in equation (2) where tau is the propeller torque, rho is freestream density, n is the rate of rotation, and D is the diameter.

Power Coefficient

Describes the propulsive power of the propeller. This relationship can be seen in equation (3) where P is the power supplied to the motor which can be found through the product of voltage and current, rho is the freestream density, n is the rate of rotation, and D is the diameter.

Advance Ratio

Describes the ratio of the freestream velocity to the tip speed of the propeller. This relationship can be seen in equation (4) where V is the freestream velocity, n is the rate of rotation, and D is the diameter.

Propeller Efficiency

Describes the power produced by the propeller with respect to the power input to the propeller, and this relationship can be seen in equation (5).