Homogeneous Bubble Nucleation driven by local hot spots: a Molecular Dynamics Study

TL;DR

This study uses molecular dynamics simulations to investigate homogeneous bubble nucleation in a Lennard-Jones fluid, revealing that local temperature fluctuations significantly influence bubble formation, which is not accounted for in classical theories.

Contribution

It demonstrates that bubble nucleation begins with compact bubbles and highlights the role of local hot spots, providing insights beyond classical nucleation theory.

Findings

Bubble nucleation starts with compact bubbles.

Nucleation rate is higher than classical predictions.

Local temperature fluctuations strongly correlate with bubble formation.

Abstract

We report a Molecular Dynamics study of homogenous bubble nucleation in a Lennard-Jones fluid. The rate of bubble nucleation is estimated using forward-flux sampling (FFS). We find that cavitation starts with compact bubbles rather than with ramified structures as had been suggested by Shen and Debenedetti (J. Chem. Phys. 111:3581, 1999). Our estimate of the bubble-nucleation rate is higher than predicted on the basis of Classical Nucleation Theory (CNT). Our simulations show that local temperature fluctuations correlate strongly with subsequent bubble formation - this mechanism is not taken into account in CNT.