Clogging of cohesive particles in a two-dimensional hopper

TL;DR

This study investigates how cohesion influences clogging in a 2D hopper using experiments and simulations, revealing that a cohesive length scale, rather than particle size, governs clogging under strong cohesion.

Contribution

It introduces a cohesive length scale that unifies experimental and simulation data, highlighting its role in clogging behavior beyond particle size.

Findings

Stronger cohesion increases clogging probability.

A cohesive length scale collapses data across parameters.

Clogging is governed by cohesive length, not particle size.

Abstract

We study clogging of cohesive particles in a 2D hopper with experiments and simulations. The system consists of buoyant, monodisperse oil droplets in an aqueous solution, where the droplet size, buoyant force, cohesion, and hopper opening are varied. Stronger cohesion enhances clogging, a trend confirmed in simulations. Balancing buoyant and cohesive forces defines a cohesive length scale that collapses the data onto a master curve. Thus, under strong cohesion, we find that clogging is governed not by particle diameter, but by the cohesive length scale.