Details of soft particle clogging in two-dimensional hoppers

Abstract

We study the outflow of soft particles through quasi-two-dimensional hoppers with both experiments and simulations. The experiments utilize spheres made with soft hydrogel, silicon rubber and glass. The hopper chamber has an adjustable exit width and tilt angle (the latter to control the magnitude of gravitational forcing). Our simulation mimics the experiments using purely two-dimensional soft particles with viscous interactions but no friction. Results from both simulations and experiments demonstrate that clogging is easier for reduced gravitational force or stiffer particles. For particles with low or no friction, the average number of particles in a clogging arch depends only on the ratio between hopper exit width and particle's diameter. In contrast for the silicon rubber particles with larger frictional interactions, arches are larger than the low friction case. Additionally, an analysis of the number of particles left in the hopper when clogging occurs provides evidence for a hydrostatic pressure effect that is relevant for the clogging of soft particles, but less so for the harder (glass) or frictional (silicon rubber) particles.

Followup to arXiv:1512.02500 (Hong et al, PRE 2017); v2 fixed bug with Gompertz distribution fits

References in corpus (4)

• Fraction of clogging configurations sampled by granular hopper flow
• Dense bubble flow in a silo: an unusual flow of a dispersed medium
• Flow in an hourglass: particle friction and stiffness matter
• Intermittent flow and transient congestions of soft spheres passing narrow orifices

Cited by in corpus (9)

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• Compression and fracture of ordered and disordered droplet rafts
• Hopper flows of dense suspensions: a 2D microfluidic model system
• Clogging-flowing transition of granular media in a two-dimensional vertical pipe
• Clogging of cohesive particles in a two-dimensional hopper