Cavitation in Centrifugal Pumps

Abstract

Abstract With the introduction of high-head centrifugal pumps of high specific speed, the problem of cavitation became of the utmost importance. As a result, extensive study and experimental work have been done in this field, mostly in connection with hydraulic turbines and with devices without moving parts. In this paper the present state of information on cavitation is presented as it applies to centrifugal pumps, with a method for determining cavitation conditions from velocity considerations. The discussion is illustrated by curves and diagrams. The model test laws as applied to cavitation are deduced, together with their limitations. Theoretical relationships governing cavitation conditions permit establishing means to avoid cavitation, which have been confirmed by experience. A summary of all important conclusions from the recent extensive literature on the subject is presented, and in conclusion, an original explanation is offered of the nature of local high destructive pressures during cavitation and in cases of metal failure by fatigue in the presence of liquids.