Surface Instability and Thermal and Cavitational Phenomena as Mechanisms of Drop Explosions in Acoustic Fountains

Abstract

A theoretical analysis is performed of the surface instability and acoustic and temperature fields in an acoustically excited drop of liquid. Such drops form in an acoustic fountain created under the action of an ultrasonic beam focused on the free boundary of the liquid. A model of a solitary spherical drop is used to describe the considered phenomena. This model is a resonator with an acoustically soft boundary, inside which a spherically symmetrical nonlinear acoustic field evolves. Mechanisms of drop explosions are proposed.