Granular discharge from concentric and eccentric wedge shaped hoppers: effect of wall friction coefficient on discharge rate

doi:10.11949/j.issn.0438-1157.20141434

Abstract

Abstract:

Particle discharging from concentric and eccentric wedge shaped hoppers with different internal friction coefficients, hopper half angles and hopper widths was simulated by 3D discrete element method (DEM) and the effect of wall friction coefficient on discharging rate were investigated. In general, increasing wall friction coefficient would decrease discharging rate by retarding particle-wall slip, and the effect was more significant in wedge shaped hoppers. The friction coefficient in the convergent section had a stronger effect in reducing discharging rate than that in the vertical section. When internal friction coefficient decreased, or the width of the hopper increased, the retarding effect would decrease and eventually become insignificant.

Key words: granular flow, computer simulation, experimental validation, discharge rate, wall friction coefficient

摘要：

采用离散元方法(DEM)研究了在不同的内摩擦系数、料仓半锥角和料仓宽度条件下,楔形中心料仓和偏心料仓中壁面摩擦系数对卸料速率的影响。研究发现,随着壁面摩擦系数的增加,两种料仓的卸料速率均先降低后稳定。当料仓从中心料仓变为偏心料仓时,壁面摩擦系数对卸料速率的影响程度以及卸料速率停止下降时的壁面摩擦系数的值都增大。随着内摩擦系数的减小或料仓半锥角的增大,壁面摩擦系数对卸料速率的影响程度以及卸料速率停止下降时的壁面摩擦系数的值都逐渐减小。增加料仓宽度能够削弱壁面摩擦系数对卸料速率的影响程度,但并不改变卸料速率停止下降时的壁面摩擦系数的值。

关键词: 颗粒流, 计算机模拟, 实验验证, 卸料速率, 壁面摩擦系数

CLC Number:

TQ018

XU Pengkai, DUAN Xuezhi, QIAN Gang, ZHOU Xinggui. Granular discharge from concentric and eccentric wedge shaped hoppers: effect of wall friction coefficient on discharge rate[J]. CIESC Journal, 2015, 66(3): 880-887.

许鹏凯, 段学志, 钱刚, 周兴贵. 楔形中心和偏心料仓中壁面摩擦系数对卸料速率的影响[J]. 化工学报, 2015, 66(3): 880-887.

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