Orientation, Flow, and Clogging in a Two-Dimensional Hopper: Ellipses vs. Disks

Abstract

Two-dimensional (2D) hopper flow of disks has been extensively studied. Here, we investigate hopper flow of ellipses with aspect ratio $\alpha =2$, and we contrast that behavior to the flow of disks. We use a quasi-2D hopper containing photoelastic particles to obtain stress/force information. We simultaneously measure the particle motion and stress. We determine several properties, including discharge rates, jamming probabilities, and the number of particles in clogging arches. For both particle types, the size of the opening, $D$, relative to the size of particles, $\ell$ is an important dimensionless measure. The orientation of the ellipses plays an important role in flow rheology and clogging. The alignment of contacting ellipses enhances the probability of forming stable arches. This study offers insight for applications involving the flow of granular materials consisting of ellipsoidal shapes, and possibly other non-spherical shapes.

6 pages, 11 figures

References in corpus (3)

• Reynolds Pressure and Relaxation in a Sheared Granular System
• Geometry dependence of the clogging transition in tilted hoppers
• Dynamics of Sheared Ellipses and Circular Disks: Effects of Particle Shape

Cited by in corpus (9)

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• Granular flow from silos with rotating orifice
• Jamming transition in non-spherical particle systems: pentagons vs. disks
• Hopper flows of deformable particles
• Stagnant Zone Formation in a 2D Bed of Circular and Elongated Grains under Penetration
• Discharge of elongated grains from silo with rotating bottom
• Stress propagation in locally loaded packings of disks and pentagons
• Controlling Colloidal Flow through a Microfluidic Y-junction
• Clogging of cohesive particles in a two-dimensional hopper