Including ionisation in a simple model of single-bubble sonoluminescence

Abstract

A small gas bubble in a liquid, when driven by intense ultrasound, collapses and emits light in a process called Single-Bubble Sonoluminescence (SBSL). While the dynamics of driven bubbles are well studied, less is known of the physical conditions in the gas or whether it is necessary to include ionisation in simpler studies of bubble dynamics. In this study, a model was derived from Rayleigh-Plesset dynamics, a van der Waals equation of state and the first law of thermodynamics (including interfacial heat transfer and ionisation). Stronger model ionisation reduced the maximum collapse temperature, and altered other collapse characteristics. Chaotic parameter regions are proximal to, but not coincident with, known stable SL regions. Resonant behaviour was only markedly affected by ionisation close to these chaotic regions.2000 Mathematics subject classification: 37N10, 76N99, 80A99, 65L07.

A simple model of magnetic fields associated with outflow from a source; new orthogonal polynomials

“…Such solutions are of importance in modelling underwater explosions, or the intriguing phenomenon of "sonoluminescence" as discussed in the review article by Brenner et al [3]. The effects of ionization in this Rayleigh-Plessett bubble model were studied by Munro and Forbes [19] and regions of chaotic behaviour in certain parameter regions were identified. More recently, cylindrical outflows from line sources in two-fluid systems with an interface have been studied by Forbes [7].…”