Photo and acoustic emissions from the non-equilibrium phase transition at the interface during cavitation

TL;DR

This paper explores the mechanisms of light and sound emissions during cavitation in water, linking them to non-equilibrium phase transitions and thermodynamic irreversibility at the cavity interface.

Contribution

It provides time-resolved measurements connecting cavitation dynamics with photo and acoustic emissions, highlighting the role of non-equilibrium phase transitions.

Findings

Emissions occur during cavity creation, expansion, and collapse.

Thermodynamic irreversibility underpins the emissions.

Emissions are linked to changes in surface entropy.

Abstract

This study investigates the emission of light and sound from cavitation caused by intense pressure pulses in water. Based on time-resolved measurements of (a) pressure waveform at the focus, (b) light scattering upon cavitation, (c) acoustic emission, and (d) photoemission (sonoluminescence) it is shown that emissions occur upon the creation or expansion as well as the collapse of the cavity. These results suggest that the thermodynamic irreversibility, resulting from non-equilibrium phase transition and changes in surface entropy, is a basis for photo and acoustic emissions during cavitation.