Obstacle-shape effect in a two-dimensional granular silo flow field

Abstract

We conducted simple experiment and numerical simulation of two-dimensional granular discharge flow driven by gravity under the influence of an obstacle. According to the previous work (Zuriguel {\it et al.,\,Phys.\,Rev.\,Lett.}\,{\bf 107}: 278001, 2011), the clogging of granular discharge flow can be suppressed by putting a circular obstacle at a proper position. In order to investigate the details of obstacle effect in granular flow, we focused on particle dynamics in this study. From the experimental and numerical data, we found that the obstacle remarkably affects the horizontal-velocity distribution and packing fraction at the vicinity of the exit. In addition to the circular obstacle, we utilized triangular, inverted-triangular, and horizontal-bar obstacles to discuss the obstacle-shape effect in granular discharge flow. Based on the investigation of dynamical quantities such as velocity distributions, granular temperature, and volume fraction, we found that the triangular obstacle or horizontal bar could be very effective to prevent the clogging. From the obtained result, we consider that the detouring of particles around the obstacle and resultant low packing fraction at the exit region effectively prevent the clogging in a certain class of granular discharge flow.

10 pages, 10 figures

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Cited by in corpus (9)

• Growth of clogs in parallel microchannels
• A counterintuitive way to speed up pedestrian and granular bottleneck flows prone to clogging: Can 'more' escape faster?
• Shape dependence of resistance force exerted on an obstacle placed in a gravity-driven granular silo flow
• Enhancement of the flow of vibrated grains through narrow apertures by addition of small particles
• The effect of obstacles near a silo outlet on the discharge of soft spheres
• Enhanced flow rate by the concentration mechanism of Tetris particles when discharged from a hopper with an obstacle
• Understanding the Local Flow Rate Peak of a Hopper Discharging Discs through an Obstacle Using a Tetris-like Model
• Elongated particles discharged with a conveyor belt in a two-dimensional silo
• Clogging-flowing transition of granular media in a two-dimensional vertical pipe