Viscoelastic bubbly media and ultrasonic shear-mode effects

TL;DR

This paper investigates how ultrasonic shear-mode effects in bubbly media influence sound propagation, revealing new resonance signatures and modifications in sound velocity due to bubble size and concentration.

Contribution

It introduces a model incorporating shear-mode effects into the analysis of bubbly media, highlighting their impact on wave behavior and resonance phenomena.

Findings

Shear-mode effects significantly alter effective wavenumber and sound velocity.

High bubble concentrations reveal additional resonance signatures.

The model predicts size-dependent resonance phenomena in bubbly media.

Abstract

Here we show that in ultrasonic fields the phenomenon of reconversion of shear-modes into an effective compressional wave has a significant effect for bubbles in a medium viscosity liquid or weak gel. We present the consequent extra terms in the effective wavenumber and find the changes in sound velocity for different bubble radii. At high concentrations of bubbles the inclusion of shear-mode effects in the multiple-scattering model can help identify bubble sizes where additional resonance signatures emerge.