Cluster Persistence: a Discriminating Probe of Soap Froth Dynamics

TL;DR

This paper investigates the decay of bubble clusters in coarsening soap froths, revealing stronger decay than models predict and highlighting the importance of T1 processes in froth dynamics.

Contribution

It introduces the concept of cluster persistence as a probe for soap froth dynamics, demonstrating its effectiveness in revealing decay behaviors and bubble motion.

Findings

Cluster decay is stronger than in existing models.

Persistent bubble fraction decreases with time.

T1 processes are significant in froth persistence.

Abstract

The persistent decay of bubble clusters in coarsening two-dimensional soap froths is measured experimentally as a function of cluster volume fraction. Dramatically stronger decay is observed in comparison to soap froth models and to measurements and calculations of persistence in other systems. The fraction of individual bubbles that contain any persistent area also decays, implying significant bubble motion and suggesting that T1 processes play an important role in froth persistence.