Influence of the solid fraction on the clogging by bridging of suspensions in constricted channels

TL;DR

This study investigates how the solid fraction of suspensions influences clogging by bridging in constricted channels, using visualization and modeling to understand the conditions leading to clog formation.

Contribution

It provides new experimental data and a stochastic model linking solid fraction to clogging probability in 3D-printed millifluidic devices.

Findings

Clogging probability increases with solid fraction.

Constricted channel width affects bridging and clog formation.

A stochastic model explains the influence of solid fraction on clogging.

Abstract

Clogging can occur whenever a suspension of particles flows through a confined system. The formation of clogs is often correlated to a reduction in the cross-section of the channel. In this study, we consider the clogging by bridging, i.e., through the formation of a stable arch of particles at a constriction that hinders the transport of particles downstream of the clog. To characterize the role of the volume fraction of the suspension on the clogging dynamics, we study the flow of particulate suspensions through 3D-printed millifluidic devices. We systematically characterize the bridging of non-Brownian particles in a quasi-bidimensional system in which we directly visualize and track the particles as they flow and form arches at a constriction. We report the conditions for clogging by bridging when varying the constriction width to particle diameter ratio for different concentrations of the particles in suspension. We then discuss our results using a stochastic model to rationalize the influence of solid fraction on the probability of clogging. Understanding the mechanisms and conditions of clog formation is an important step for optimizing engineering design and developing more reliable dispensing systems.