A Model for the Elasticity of Compressed Emulsions
Martin-Daniel Lacasse, Gary S. Grest, Dov Levine, T.G. Mason, D.A. Weitz
Abstract
We present a new model to describe the unusual elastic properties of compressed emulsions. The response of a single droplet under compression is investigated numerically for different Wigner-Seitz cells. The response is softer than harmonic, and depends on the coordination number of the droplet. Using these results, we propose a new effective inter-droplet potential which is used to determine the elastic response of a monodisperse collection of disordered droplets as a function of volume fraction. Our results are in excellent agreement with recent experiments. This suggests that anharmonicity, together with disorder, are responsible for the quasi-linear increase of
G
and
Π
observed at
φ
c
.