Some compressibility effects in cavitation bubble dynamics

[摘要] 1. Theories on the dynamics of cavitation are criticallyexamined, and are found to need clarification.2. The contents of a bubble formed from a submicroscopicnucleus are agreed to be almost entirely water vapor.This water vapor is shown to be unable to offer decisiveresistance to inward flow during the finite portion ofthe collapse.3. The effect of compressibility of the liquid is analyzedin detail. It is found to reduce velocities noticeably,but does not, in itself, eliminate the anomaly of an infinite collapse velocity as the bubble radius approacheszero. The pressures in the fluid surrounding the bubbleare found to be markedly reduced by the assumption ofcompressibility.4. Energy is found to be continually transported inwardduring the collapse period.5. The mechanism of rebound of a compressible liquid isexamined when the bubble collapse is arrested by an immovable barrier of finite radius. A shock wave is formedfollowed by a tension wave responsible for rupturing theliquid.6. The shock wave is estimated to carry off 47% of availableenergy, and limit rebound to 81% of former size.7. The maximum pressure in the outgoing shock wave isfound to be incapable of damaging a metallic wall whenthe point of collapse is not on that boundary.

[发布机构] University:California Institute of Technology;Department:Engineering and Applied Science

[关键词] Mechanical Engineering