Description: Rotor resonant frequency calculated assuming that the rotor is supported only in the bearings and that the bearings have infinite stiffness; Name: crit speed (dry)
Description: Rotor resonant frequency calculated considering the additional support and damping produced by the action of the pumped fluid within rotor  ; Name: Wet critical speed
Description: translation i of a pair of gears or a multiple gear pair is the ratio of the angle speed wa (or the speed na) of the first driving wheel to that of the last driven wheel wb (or nb); Name: Transmission ratio of the transmission