Cavitation damage in a centrifugal pump impeller eye occurs primarily when the local absolute fluid pressure falls below:
Options:
(A) Atmospheric pressure
(B) The saturated vapour pressure of the liquid at operating temperature
(C) The discharge cut-off pressure
(D) The critical Reynolds pressure
Answer Key:
B
Step-by-Step Solution & Explanation
When local static pressure drops below the saturated vapour pressure corresponding to the liquid temperature, vapour pockets/cavities form. As these bubbles travel into higher pressure regions, they implode violently, pitting and eroding the impeller metal.