颗粒缩放理论标定未筛选烟煤离散元仿真参数  

Discrete elemental simulation parameters of unscreened bituminous coal calibrated by particle scaling theory

作　　者：梅潇[1] 吴苇荣 刘祥伟 MEI Xiao;WUWeirong;LIU Xiangwei(Logistics Engineering College,Shanghai Maritime University,Shanghai 201306,China)

机构地区：[1]上海海事大学物流工程学院,上海201306

出　　处：《中国粉体技术》2024年第2期67-81,共15页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:52105466;上海科委浦江人才计划项目,编号:21PJ1404600。

摘　　要：【目的】为了给未筛选烟煤的仿真研究提供参数依据,分析未筛选烟煤的离散元仿真参数,保证仿真与实际颗粒的几何、材料及运动学相似,实现未筛选烟煤的可靠仿真研究。【方法】采用实验和仿真相结合的方法,测得未筛选烟煤的粒径分布、密度、静摩擦因数、堆积密度、休止角等基本参数;基于颗粒缩放理论,建立不同粒径范围内典型颗粒的放大模型,通过Plackett-Burman、最陡爬坡、 Box-Behnken试验对未筛选烟煤的泊松比、切变模量、滚动摩擦因数、恢复系数、 Johnson-Kendall-Roberts(JKR)表面能等仿真参数进行标定。【结果】以实验和仿真休止角相对误差最小为优化目标,得到最优参数组合下的未筛选烟煤的仿真休止角为37.59°,与休止角实验值37.81°的误差为0.58%;仿真堆积密度为717 kg/m^(3),与堆积密度实验值722 kg/m^(3)的误差为0.69%。【结论】煤-煤恢复系数与休止角呈负相关,煤-煤和煤-钢滚动摩擦因数与休止角呈正相关,溅射现象会阻碍颗粒堆积。Objective In recent years, the proportion of coal in port traffic has been increased. Unscreened bituminous coal, as an important fuel for power plants or industrial boilers, is one of the widely utilized coal types. Therefore, conducting simulation studies on the transport process of unscreened bituminous coal holds extreme importance. However, according to different simulation conditions, it is usually necessary to scale the particle size of unscreened bituminous coal to meet various simulation requirements. The validity of setting particle discrete element simulation parameters directly affects the accuracy of the simulation results. To obtain discrete elemental simulation parameters for unscreened bituminous coal particles after scaling processing, the simulation parameters should be calibrated to ensure that it meets the geometric similarity, material similarity and kinematic similarity with the actual particles.Methods In this study, optimal parameter combinations for the discrete element simulation of unscreened bituminous coal were determined through a combination of physical experiments and simulation. Firstly, the basic parameters of bituminous coal, such as particle size distribution, density, static friction coefficients, bulk density, and angle of repose, were determined through physical experiments. Subsequently, typical particle models within different particle size ranges were established and the particle sizes were magnified by a factor of five using particle scaling theory principles. This approach aimed to shorten simulation time and reduce the computational demands on the computer performance during simulations. Following this, the Plackett-Burman(P-B) test was employed to analyze the significance of calibration parameters, including Poisson's ratio, shear modulus, rolling friction coefficient, restitution coefficient and Johnson-Kendall-Roberts(JKR) surface energy. The steepest ascent test was then utilized to quickly determine the range of optimal parameter combinations for the simulated ang

关 键 词：烟煤 离散元 休止角 颗粒缩放理论 参数标定 

分 类 号：TB44[一般工业技术] TP391.9[自动化与计算机技术—计算机应用技术] O347.7[自动化与计算机技术—计算机科学与技术]