Propeller thrust and torque
Use measured or validated coefficients at your operating advance ratio.
Thrust (N):
Torque (N·m):
Advance ratio J:
Shaft power (kW):
Open-water efficiency:
Equations and assumptions
With n = RPM / 60: T = KT ρ n² D⁴; Q = KQ ρ n² D⁵; J = Va / (n D); shaft power = 2πnQ. Efficiency = TVa / (2πnQ).
KT and KQ must describe the same propeller at the entered J and applicable operating conditions. This tool does not infer them from blade count or pitch. The previous unsupported coefficient approximation has been removed. It does not predict cavitation or installed vessel performance.
Reference: MIT, Performance of Propellers.