基于离散元法的煤颗粒模型参数优化

Optimization method for coal particle model parameters based on discrete element method

为更加真实地模拟煤矿机械和煤散料相互作用,基于离散元法对煤颗粒模型参数进行优化;针对煤颗粒的非规则形状,建立3种颗粒模型;设计一系列实验测定煤颗粒的密度、煤颗粒与耐磨钢板间的恢复系数和静摩擦系数、煤颗粒间的恢复系数;设计响应面仿真试验,建立回归模型并进行优化,以实验获得的煤散料堆积角作为响应值,优化确定煤颗粒间静摩擦系数、滚动摩擦系数以及煤与耐磨板钢间的滚动摩擦系数;最后通过设计的滑板装置将优化参数组合下的仿真与实验结果进行对比验证。结果表明,堆积角数值差异是1.3%,提高了仿真结果的可靠性。

In order to simulate the interaction more accurately between coal mining machinery and coal bulk materials,the parameters of coal particle model were optimized based on discrete element method(DEM).Considering the irregular shape of coal particles,three kinds of particle models were established.A series of actual tests were carried out to measure the density of coal particle,the coefficient of restitution and the coefficient of static friction between coal and wear-resistant steel plate,the coefficient of restitution between coal particles.The accumulation angle obtained by actual test was taken as the response value,the coefficient of static friction and the coefficient of rolling friction among particles and the rolling friction coefficient between particle and wear-resistant steel plate were determined through the response surface method.Through the skateboard device,the optimal parameter combination was validated by comparing the simulation results with actual tests.Results showed that the numerical difference in accumulation angle of actual tests and simulation is 1.3%,which improves the reliability of simulation results.