Description: Ratio of the power requirement of the pump reduced by the mechanical power losses  to the power requirement of the pump under certain working conditions.; Name: mech eff
Description: proportion of the pump power input, p, available after satisfying the mechanical power losses, pj,ab, at given operating conditions; Name: mechanical efficiency
Description: amount of the absolute value of the total head above the head, equivalent to the vapour pressure of the liquid at the particular temperature, with reference to the NPSH datum plane; Name: net positive suction head