Deposition of Charged Micro-Particles on Fibers: Clogging Problem

Abstract

We perform computer simulations based on adhesive contact mechanics to investigate the clogging process of charged micro-particles at single-pore level. The effect of long-range Coulomb repulsion on clogging is characterized in terms of bulk permeability, the number of penetrating particles, and the particle capture efficiency. Results indicate that the repulsion among particles delays or even totally prevents the formation of clogs. A clogging phase diagram, in the form of the driving pressure and a proposed charge parameter, is constructed to quantify the clogging/non-clogging transition. A critical state, where the capture efficiency of particles decreases to its minimum, is identified as a clogging/non-clogging criterion for repulsive particles. The distributions of local volume fraction show that the structure of clogs is mainly determined by the short-range adhesion. With a relatively strong adhesion, a loose clog will be formed and is easier for particles to penetrate. Finally, a schematic representation of the clogging process, considering both the long-range repulsion and the adhesion, is proposed to show the relationship between the clogging results and the inter-particle interactions.