Pump Losses

The shaft power or energy that is supplied to the pump by the prime mover is not the same as the energy received by the liquid, some energy is dissipated as the liquid passes through the machine.

The mechanism of the loss in a pump:

1. Mechanical friction power loss due to friction between the fixed and rotating parts in the bearing and boxes
2. Leakage and circulating power loss due to a loss of liquid from the pump or circulation of the liquid in the impeller
3. Disc friction power loss due to friction between the rotating faces of the impeller and the liquid.
4. Casing power loss