The effect of surface-active solutes on acoustic cavitation bubble populations

Abstract

Ultrasound in liquids can cause bubbles to grow to the resonance size via either the process of rectified diffusion or bubble-bubble coalescence. At the resonance size bubbles collapse and emit light, known as sonoluminescence (SL). In this study the effect of surface-active solutes on the initial growth of the active bubble population in the presence of ultrasound (a train of 4 ms pulses of 515 kHz) was monitored. This was achieved by following the SL intensity emitted by the active bubbles, until an equilibrium population of active bubbles was reached, as indicated by a maximum SL intensity. The number of pulses required to reach the maximum SL intensity was found to increase with increasi..