多漏斗放矿过程中散体介质力链演化特征量化研究

Quantitative study on evolution characteristics of force chain of granular materials in ore drawing from multiple funnels process

借助离散元软件,对多漏斗放矿过程中矿石散体介质体系内部力链数量、长度、强度、方向等演化特征进行量化研究。研究结果表明:在多漏斗放矿过程中,力链数量总体上呈指数形式减少,且不同放矿节点条件下力链长度的概率分布也均呈指数形式减少;力链强度波动范围较大,总体上随放矿次数增加而呈指数形式减少。不同放矿节点条件下力链强度的概率分布规律具有一致性,即先呈指数形式上升,后呈指数形式下降。在放矿前中期,散体介质体系内部力链分布主方向角θ_(n)始终保持在90°左右,各向异性程度表征参数β_(n)逐渐增大,表现出明显的各向异性;在放矿后期,与水平方向呈45°的力链逐渐增多,体系内部力链分布主方向角θ_(n)由84.40°变化为30.16°,各向异性程度表征参数β_(n)逐渐减小。

With the help of the discrete element software, the evolution characteristics of the force chain such as the number, length, strength and direction of the ore granular materials system in the process of ore drawing from multiple funnels were quantitatively studied. The results show that in the process of ore drawing from multiple funnels, the number of force chains decreases exponentially, and the probability distribution law of force chain length at different drawing nodes also decreases exponentially. In the process of ore drawing, the fluctuation range of force chain strength is large, and it decreases exponentially with the increase of drawing times. The probability distribution law of force chain strength under the conditions of different ore drawing nodes is also consistent,which increases firstly in exponential form and then decreases in exponential form. In the early and middle stage of ore drawing, the main direction angle of force chain distribution in the granular materials system stays around 90° and the anisotropy degree characterization parameter β_(n) increases gradually, showing obvious anisotropy. In the later stage of ore drawing, the force chain with 45° to the horizontal direction increases gradually, the main direction angle θ_(n) of force chain distribution in the system changes from 84.40° to 30.16°, and the anisotropy degree characterization parameter β_(n) decreases gradually.