Affine and non-affine motions in sheared polydisperse jammed emulsions

TL;DR

This study investigates how dense, polydisperse emulsions respond to shear, revealing that droplet size disparity influences motion patterns, with larger droplets affecting smaller ones and correlations extending over multiple droplet diameters.

Contribution

It provides new insights into the complex affine and non-affine motions in highly polydisperse emulsions under shear, highlighting the impact of droplet size disparity on dynamics.

Findings

Smaller droplets exhibit more nonaffine motion due to larger droplets.

Droplet motions are correlated over length scales up to four times the mean droplet size.

Higher strain amplitudes increase the correlation length scale.

Abstract

We study dense and highly polydisperse emulsions at droplet volume fractions \phi >= 0.65. We apply oscillatory shear and observe droplet motion using confocal microscopy. The presence of droplets with sizes several times the mean size dramatically changes the motion of smaller droplets. Both affine and nonaffine droplet motions are observed, with the more nonaffine motion exhibited by the smaller droplets which are pushed around by the larger droplets. Droplet motions are correlated over length scales from one to four times the mean droplet diameter, with larger length scales corresponding to higher strain amplitudes (up to strains of about 6%).