Abstract:

Based on the single-bubble and double-bubble ultrasonic cavitation noise models derived respectivelyfrom the single-bubble and double-bubble dynamic equation and from the Lighthill equation,the effects of the initialbubble radius,the double-bubble distance,the sound pressure amplitude,the sound frequency and the bifrequencyultrasound on the cavitation noise are analyzed via Matlab programming.Calculated and analytical resultsshow that ( 1) under the same initial conditions,the peak of the double-bubble cavitation noise is much higher thanthat of the single-bubble one,which means that the single-bubble and double-bubble cavitation noise curves are differentform each other; ( 2) the initial radius,the sound pressure amplitude,the sound frequency and the bifrequencyultrasound all affect the single-bubble cavitation noise,especially the former two; ( 3) the cavitation noisereaches the maximum when the pressure amplitudes in the two components of the bifrequency ultrasound are equal;and ( 4) the initial radius and the sound pressure amplitude influence the double-bubble cavitation noise significantlywhile the effects of the sound frequency and the bifrequency ultrasound are almost ignorable.

Key words: bifrequency ultrasound, cavitation noise, single bubble, double bubble