Description: 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. ; Name: crit. speed
Description: Speed of rotation at which the frequency of vibration (or its multiples) corresponds to the rotor resonant (lateral or torsional) ; Name: Critical speed
Description: Determined proportion of pump available power input, Pa, which is delivered as pump power output, Pu, after satisfying the losses resulting from friction due to the relative motion of internal surfaces and internal leakage ; Name: Hydraulic efficiency