多漏斗放矿过程散体介质接触力特性量化研究

Quantitative study on contact force characteristics of granular medium in multi-funnel ore drawing process

本文基于离散元软件,开展多漏斗放矿过程中散体介质接触力特性的量化研究。结果发现:放矿过程中,散体介质内部越靠近底部接触力集度越大,不同类型接触力概率分布均呈指数式衰减,且接触力强度的分布规律也具有较高的相似性;放矿前中期接触力网络的方向偏向y轴方向(铅垂方向),随着矿石颗粒不断放出,接触力网络方向逐渐偏向x轴方向(水平方向);放矿初期,接触力沿y轴方向较大,沿x轴方向接触力较小,法向接触力主要集中在铅垂方向;直至放矿中期,与水平方向夹角为30°的法向接触力逐渐增多,接触力分布的主方向由一个变为三个;放矿后期,与水平方向呈45°夹角的法向接触力逐渐增多,接触力分布方向由三个转变为六个。

In this paper,the quantitative study of contact force characteristics of granular materials in multi-funnel ore drawing process was carried out based on discrete element software.The results show that,during the process of ore drawing,the closer to the bottom of the granular materials,the greater the contact force concentration;the probability distribution of different types of contact force in the process of ore drawing is in exponential form,and distribution law of contact force intensity is highly similar under the conditions of different drawing nodes.The direction of contact force network inside the granular materials is inclined to the y-axis direction(vertical direction)during the initial stage and medium stage of ore drawing,with the increase of ore drawing times,the direction of contact force network inside the granular materials is gradually inclined to the x-axis direction(horizontal direction).At the initial stage of ore drawing,the normal contact force shows obvious anisotropy,that is,the contact force along y-axis is larger than the contact force along x-axis direction,and the normal contact force mainly concentrates in the vertical direction.With the increase of ore drawing times,the normal contact force with an inclination angle of 30°to horizontal direction increases gradually,and the main distribution direction of contact force changes from one to three.At the later stage of ore drawing,the normal contact force with an inclination angle of 45°to horizontal direction increases gradually,and the distribution direction of normal contact force changes from three to six.