Cavitation
Cavitation is a buildup of cavities, or bubbles, within the liquid being pumped, that form at low pressure. When the cavities within the liquid are passed through the pump from low pressure areas into high pressure areas, they cause problems with the pump.
Problems
The process of cavitation in submersible water pumps can produce inconsistent water pressure and a reduced efficiency for the pump. Other problems associated with cavitation include noise, vibration and damage to the submersible pump.
Causes
The causes of cavitation include vaporization, internal recirculation, flow turbulence and vane passing syndrome (cavitation resulting from the small size of the impeller or low cutwater clearance). Another problem with cavitation is air ingestion, whose symptoms are similar to cavitation.