­­Suction Specific Speed (S)

Suction Specific Speed (S) like Impeller Specific Speed (Ns) is a parameter, or inde­x of hydraulic design describing the suction capabilities and characteristics of a given first stage impeller. Input values for Flow and NPSHR that correspond to the the pump performanc­e at optimum (or best) efficiency point. In this example, calculate the suction specific speed­ in either Metric or US units.