Damage Due to Cavitation and Sub-Cooled Boiling Bubble Collapse

Abstract

The possibility of the applicability of spherical symmetry to cavitation and highly sub-cooled bubble collapse is considered in the light of present photographic and theoretical evidence, and it is concluded that such symmetry is unlikely in situations of engineering importance. Rather an asymmetry which generates a high-velocity microjet is a more likely mode of collapse. The present evidence relative to the importance of microjet impact as opposed to the classical spherical shock-wave model for cavitation damage is examined and some new experimental evidence presented. It is concluded that the microjet model is most likely of predominant importance in cavitation damage. Some estimates for the pertinent parameters of such microjets are presented.