Acoustic Waves Forced in Flowing Bubbly Liquid

Abstract

The initial-boundary value problem is solved for acoustic disturbance caused by a source in the uniform bubbly liquid flow without the velocity slip. The solution shows the transient and final characteristics of four modes of unusual acoustic wave, resulting from the interaction between the volume oscillation of bubbles and the wave motion in the flowing medium. The solution also shows that the energy distributed for each mode is different depending on the frequency of the source and on Mach number of the main stream. For high frequency, the ratio of propagation mode to cutoff mode is very small at low Mach number but large at high Mach number. There is a possibility that the energy of cutoff modes is expended to break up bubbles.