Bubble dynamics in fluids with N-body simulations

TL;DR

This paper introduces a particle-based simulation method to study bubble dynamics in fluids, especially where traditional perfect fluid models are inadequate, and examines how self-interactions influence bubble wall velocity and fluid profiles.

Contribution

The paper presents a novel N-body simulation approach for bubble dynamics that captures effects beyond perfect fluid assumptions, including self-interactions and local thermal equilibrium.

Findings

Self-interactions can maintain local thermal equilibrium around the bubble wall.

Fluid profiles in strongly self-interacting fluids resemble perfect fluid results.

The method is applicable to cases where traditional models fail.

Abstract

We present a new approach to studies of bubble dynamics in fluids. Relying on particle-based simulations, this method is general and suitable for cases where the commonly used perfect fluid description fails. We study expanding true vacuum bubbles surrounded by free or self-interacting particles and quantify how self-interactions affect the terminal bubble wall velocity. We find that, for sufficiently strongly self-interacting fluids, local thermal equilibrium is maintained around the bubble wall and the fluid profile is similar to that obtained with the perfect fluid description.