Enhanced Coalescence in Driven Foams

TL;DR

This paper investigates how mechanical vibration enhances bubble coalescence in driven quasi-2D foams, revealing how external driving and liquid properties influence foam structure and dynamics.

Contribution

It introduces a statistical model that quantitatively describes the interplay of coarsening and coalescence under external vibration in foams.

Findings

Vibration significantly increases bubble coalescence.

The competition between coarsening and coalescence can be controlled.

A statistical model accurately predicts bubble number evolution.

Abstract

External driving leads to the emergence of unique phenomena and properties in soft matter systems. We show that driving quasi-2D foams by mechanical vibration results in significant bubble coalescence, which is enhanced by the continuous phase yield stress. The competition between coarsening and coalescence can be modulated through vibration amplitude and foam liquid fraction, which can be used to create unusual structural motifs. The combined effect of coarsening and coalescence is captured through a statistical model that quantitatively describes the time evolution of the number of bubbles.