Authors

Abstract

For the problem of lacking reliable parameters during simulation analysis of the crushed corn stalk (CCS) micro-comminution process with gas-solid coupling method, the simulation parameters are calibrated using a combination of physical measurements and virtual experiments with CCS as the research object. The intrinsic parameters of CCS are obtained by physical experiment, and the stacking test is carried out by cylinder lifting method, and the actual angle of repose(AoR) is obtained as 44.12° by fitting the boundary line with Matlab software; the discrete element model of CCS is established, and the virtual stacking test is carried out by EDEM software; CCS-CCS dynamic friction coefficient, CCS-CCS static friction coefficient and JKR (Johnson-Kendall-Roberts) surface energy are identified as the parameters with significant effects on the AoR by Plackett-Burman test; the steepest climb test is leveraged to determine the center of response surface analysis; the quadratic polynomial regression model of the simulation parameters and the AoR is established by the Box-Behnken test using the AoR as the evaluation index, and the optimal combination of the significant parameters are obtained as follows: the CCS-CCS dynamic friction coefficient is 0.55, the CCS-CCS static friction coefficient is 0.14, and the JKR surface energy is 0.12; the AoR verification test is conducted based on the optimal combination of the significant parameters The results show that the AoR of the CCS is 43.82°, which is 0.68% of the actual AoR, indicating that the parameter combination is reliable. The data obtained in this research can provide corresponding simulation parameters for CCS discrete element simulation and the development of straw micro-crushing equipment.

Abstract in Chinese

针对采用气固耦合法对碎玉米秸秆微粉碎过程仿真分析时，所需的仿真参数缺乏可靠数值的问题，以碎玉米秸秆为研究对象，采用物理测定与虚拟试验相结合的方法对仿真参数进行标定。通过物理试验获取碎玉米秸秆的本征参数，采用圆筒提升法进行堆积试验，并利用Matlab软件拟合边界线得到实际休止角为44.12°；建立碎玉米秸秆离散元模型，利用EDEM软件进行虚拟堆积试验；通过Plackett-Burman试验，确定对休止角影响显著的参数为碎玉米秸秆间滚动摩擦因数、碎玉米秸秆间静摩擦因数和JKR（Johnson-Kendall-Roberts）表面能；利用最陡爬坡试验，确定响应面分析的中心；以休止角为评价指标，通过Box-Behnken试验建立显著参数与碎秸秆休止角的二次多项式回归模型，对显著参数的取值进行寻优，得到较优的显著参数组合为：碎玉米秸秆间滚动摩擦因数为0.55、碎玉米秸秆间静摩擦因数为0.14、JKR表面能为0.12；基于最优参数组合进行休止角验证试验，试验结果表明，该参数组合下碎玉米秸秆的休止角为43.82°，与实际休止角误差为0.68%，表明该参数组合具有可靠性。本文得到的数据可为碎玉米秸秆离散元仿真以及秸秆微粉碎设备的研发提供相应的仿真参数。