Shape dependence of resistance force exerted on an obstacle placed in a gravity-driven granular silo flow

Abstract

Resistance force exerted on an obstacle in a gravity-driven slow granular silo flow is studied by experiments and numerical simulations. In a two-dimensional granular silo, an obstacle is placed just above the exit. Then, steady discharge flow is made and its flow rate can be controlled by the width of exit and the position of obstacle. During the discharge of particles, flow rate and resistance force exerting on the obstacle are measured. Using the obtained data, a dimensionless number characterizing the force balance in granular flow is defined by the relation between the discharge flow rate and resistance-force decreasing rate. The dimensionless number is independent of flow rate. Rather, we find the weak shape dependence of the dimensionless number. This tendency is a unique feature for the resistance force in granular silo flow. It characterizes the effective flow width interacting with the obstacle in granular silo flow.

8 pages, 8 figures

References in corpus (8)

• Unified force law for granular impact cratering
• Obstacle-shape effect in a two-dimensional granular silo flow field
• Sensitivity of Granular Force Chain Orientation to Disorder-induced Metastable Relaxation
• The Physics of Protoplanetesimal Dust Agglomerates. X. Mechanical properties of dust aggregates probed by a solid-projectile impact
• Force Chain Evolution in a Two-Dimensional Granular Packing Compacted by Vertical Tappings
• Scaling law of the drag force in dense granular media
• Statistical properties of gravity-driven granular discharge flow under the influence of an obstacle
• Geometry-dependent constitutive law for granular slow frictional drag