Authors

Abstract

This paper addresses the problem of the lack of intrinsic and contact parameters when applying the discrete element method to simulate and analyze the key aspects of white kidney bean seed sowing, harvesting and clearing. The experiment took white kidney bean seeds as the research object, measured the intrinsic parameters of white kidney bean seeds by using the universal testing machine, and measured the collision recovery coefficient of 0.445, static friction coefficient of 0.452 and rolling friction coefficient of 0.091 between white kidney bean seeds and Q235 steel plate by physical test and EDEM discrete element simulation parameter calibration. The stacking experiment was carried out by the cylinder lifting method, numerical processing was performed with MATLAB, and the actual stacking angle of white kidney bean seeds was 31.28°. The steepest climbing test was designed with the interspecific contact parameters as factors and the relative error between the actual and simulated stacking angles as indicators. The optimal combination of the interspecific contact parameters of white kidney bean was determined by response surface optimization analysis, and the interspecific collision recovery coefficient of white kidney bean was obtained as 0.39, static friction coefficient was 0.53, rolling friction coefficient was 0.092. Using the optimal parameters for the simulation test, the relative error between the actual stacking angle of white kidney bean seeds and the simulated stacking angle was 1.63%, indicating that the calibrated simulated contact parameters were reliable and could provide reference for the discrete element simulation of white kidney bean seeds.

Abstract in Chinese

针对应用离散元法对白芸豆播种、收获和清选等关键环节进行仿真分析时，缺乏本征参数和接触参数的问题。该实验以白芸豆种子为研究对象，使用万能试验机测得白芸豆种子本征参数，通过物理试验和EDEM离散元仿真参数标定，测定白芸豆种子与Q235钢板之间的碰撞恢复系数为0.445、静摩擦系数为0.452、滚动摩擦系数为0.091。采用圆筒提升法进行堆积试验，用MATLAB对堆积图像进行数值处理，得到白芸豆种子实际堆积角为31.28°。以种间接触参数为因素，以实际堆积角和仿真堆积角的相对误差为标准，进行最陡爬坡试验，通过响应面优化分析确定白芸豆种间接触参数最优组合，确定白芸豆种间碰撞恢复系数为0.39， 静摩擦系数为0.53，滚动摩擦系数为0.092。利用最优参数进行仿真验证，结果显示白芸豆种子实际堆积角与仿真堆积角相对误差为1.63%，表明所标定的接触参数具有可靠性，可为白芸豆种子离散元仿真提供参考。