Critical Speed of a Rotating Shaft - Dunkerley's method


In solid mechanics, in the field of rotordynamics, the critical speed is the theoretical angular velocity that excites the natural frequency of a rotating object, such as a shaft, propeller, leadscrew, or gear.

Dunkerley’s method is used in mechanical engineering to determine the critical speed of a shaft-rotor system.

Related formulas


Ncritical speed(r.p.m.) (1/s)
Eyoung's modulus (pascal)
ISecond moment of area (m4)
mmass of the shaft (kg)
Llength of the shaft between points (m)