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: net positive suction head (NPSH) from flow rate at best efficiency point for actual impeller (indication of the minimum inlet pressure in meters required for the pump to deliver according to the QH curve. related to the optimum duty point at the current impeller diameter); Name: net positive suction head for Q opt at actual impeller size