Ideal wet two-dimensional foams and emulsions with finite contact angle

TL;DR

This paper uses simulations to show that two-dimensional foams with a finite contact angle naturally develop inhomogeneities at high liquid fractions, similar to flocculation in emulsions, especially in disordered structures.

Contribution

It demonstrates that inhomogeneity in 2D foams with finite contact angles arises spontaneously at high liquid fractions, expanding understanding of foam and emulsion behaviors.

Findings

Inhomogeneity develops spontaneously in disordered foams at high liquid fractions.

Ordered foams require perturbations for inhomogeneity to appear.

Simulations with Surface Evolver confirm the inhomogeneity growth.

Abstract

We present simulations that show that an ideal two-dimensional foam with a finite contact angle develops an inhomogeneity for high liquid fraction $\phi$. In liquid-liquid emulsions this inhomogeneity is known as flocculation. In the case of an ordered foam this requires a perturbation, but in a disordered foam inhomogeneity grows steadily and spontaneously with $\phi$, as demonstrated in our simulations performed with the Surface Evolver.