二维颗粒流通道宽度效应的分子动力学模拟

通过用分子动力学方法对颗粒物质流的计算机模拟，研究发现增大通道宽度可以使二维颗粒流从稀疏流转变为密集流状态.通过对不同通道宽度下，固定开口为9.5d的颗粒流和 漏斗口以上9.5d×8d区域记录的模拟结果分析，发现随通道宽度增大，密度变大、温 度降低.当“颗粒温度”T较低时(T/m<0.05 J/kg),颗粒流内部接触数开始超过1.2 ，同时出现较为牢固的横向链状颗粒团簇，是造成流量突变以及密集流的原因.关键词：颗粒物质颗粒流计算机模拟

The molecular dynamics simulation of the effect of channel width on two-dimensional granular flow

In this paper,we use the molecular dynamics simulation to study the phenomena that the granular flow changes from dilute flow to dense flow by increasing the channel width at a fixed orifice of 9 5 d (d is the diameter of grains). In the area over the orifice,the density of flow increases and the granular temperature decreases with the increase of channel width. The change from dilute flow to dense flow begins at a channel width of 24 d ,a lower granular temperature( T/m =0 05 J/kg) and a larger coordination number of 1 2 The mechanism is a structural change in the granular flow,since a wider channel results in more horizontal chains of particles and a lower temperature makes these chains more stable.