# Shear-wave generation from cavitation in soft solids

## TL;DR

This paper investigates how cavitation in elastic solids, such as soft tissues, can generate shear waves during cavity collapse, with implications for medical therapies and tissue damage.

## Contribution

It demonstrates that cavitation in elastic solids emits shear waves, a phenomenon previously observed mainly in liquids, and explores its potential impact on soft tissue injury.

## Key findings

- Cavitation in elastic solids produces shear waves during cavity collapse.
- Shear wave origin is linked to cavity dynamics near boundaries.
- Surface deformation and crack formation are observed during cavitation.

## Abstract

The formation and dynamics of cavities in liquids leads to focusing of kinetic energy and emission of longitudinal stress waves during the cavity collapse. Here we report that cavitation in elastic solids may additionally emit shear waves that could affect soft tissues in human bodies/brains. During collapse of the cavity close to an air-solid boundary, the cavity moves away from the boundary and forms a directed jet flow, which confines shear stresses in a volume between the bubble and the free boundary. Elastographic and high-speed imaging resolve this process and reveal the origin of a shear wave in this region. Additionally, the gelatin surface deforms and a conical crack evolves. We speculate that tissue fracture observed in medical therapy may be linked to the non-spherical cavitation bubble collapse.