Influence of characteristic parameters on the void rate in an acoustic cavitation bubble field

摘要

Among the causes of the cavitation effects dispersion. bubble field plays an important role. Not only are its bubbles responsible for most of the effects, but moreover they modify the wave which activates them. It is difficult to determine thebubble sizes and their distribution, but their overall volume can be determined with a hyper-frequency technique presented in this paper. The void rate is not described in any' ultrasonic cavitation or bubble-wave interaction theory. Nevertheless, itsdetermination is an innovative and important tool to describe and to characterize bubble fields in ultrasonic cavitation phenomena. Maximum void rate evolution is examined as a function of the insonification duration, of the acoustic pressure amplitudeand of the initial air content in water.