Flow and clogging of explicitly deformable particles

Flow-induced jamming, or clogging, is observed across a wide range of systems, from flows of granular materials in silos to flows of emulsion droplets through microfluidic chambers. While there have been significant advances in the understanding of clogging in granular materials with hard particles, little is known about clogging when the particles can change their shapes in response to applied stress. To understand flow and clogging in systems composed of deformable particles, we carry out discrete element method (DEM) simulations of shape-changing particles flowing through hoppers under the influence of a body force. We compare these results to simulations of soft particles with fixed reference shapes flowing through hoppers. We measure the clogging probability as a function of the orifice opening and particle stiffness, characterize the multi-particle structures that give rise to clogs, and correlate changes in particle shape to particle motion that relieves temporary clogs. In addition, we compare the particle flow rate and shape distribution in the simulations to experimental studies of emulsion droplets flowing through quasi-2D microfluidic channels.