【摘要】 为了研究自然崩落法放矿场中崩落矿岩的动力学响应机理,将碎石细颗粒流与大块矿岩分别视为非牛顿流体与离散体,并基于LBM-DEM耦合方法实现自然崩落法放矿模拟。从放矿动力学角度对单个矿岩颗粒进行受力分析,根据动量定理推导出总摩擦力及力矩计算公式,并求得颗粒运动方程;根据某矿放矿参数建立单漏斗放矿模型。研究结果表明:放矿口上部存在松散与压缩2种变形,且放矿场内压力因散体矿岩的随机脉动形式随时间呈脉动分布;不同监测点处的压力均在一定的区间内波动,主要与颗粒间的摩擦与碰撞作用产生能量传递与能量耗散有关。该耦合模拟方法在细观尺度上为散体矿岩与细颗粒流的动力学作用分析提供一种新的研究手段,并对研究放矿成拱原因及控制底部结构压力等有指导作用。更多还原

【Abstract】 To investigate the dynamics response mechanism of caved rock in block caving ore-drawing field,fine particle flow and granular ore-rock are considered as non-newtonian fluid and discrete element bulks,respectively. A simulation model of block caving ore-drawing is established based on coupling of LBM-DEM. Through analyzing force state on single granular ore-rock particle from the view of ore-drawing dynamics,total friction force and torque calculation formulas are deduced according to theorem of momentum and the particle motion equation is concluded. A single-funnel ore-drawing model is generated according to the ore-drawing parameters in a certain mine. The results indicate that the loose and compression deformations exist at upper part of ore-drawing point and the pressure in ore-drawing field makes pulse distribution with time as granular ore-rock pulses in random. Pressure values at different monitoring points are fluctuated in a certain interval,which is mainly related to the energy transfer and dissipation caused by the friction and collision action between particles. This coupling method provides a new research method for analyzing dynamics action between granular ore-rock and fine particle on meso-scale,and plays a guiding role in analyzing the cause for arching during ore-drawing and controlling the pressure in bottom structure.更多还原