Authors

Abstract

To address the lack of contact parameters between Corydalis tuber and mechanical, soil interfaces during planting, harvesting, and processing stages, this study calibrated discrete element simulation parameters for Corydalis tuber by combination of simulation tests and physical tests. 3D contour model of Corydalis tuber was obtained via 3D scanning technology, and a multi-sphere bonded particle model of Corydalis tuber was constructed by automatic filling method. Simulation tests were conducted with the restitution coefficient, static friction coefficient, and rolling friction coefficient between Corydalis tuber and Q235 steel, as well as between Corydalis tuber and soil, as independent variables. The rebound height, friction angle, and rolling distance were used as dependent variables. A second-order polynomial fitting method was applied to the experimental results. The actual test values were substituted into the polynomial equations to obtain simulation values for the contact parameters of Corydalis tuber with Q235 steel and soil, and these values were then validated against the experimental results. The findings indicate that the restitution coefficients of Corydalis tuber-Q235 steel and Corydalis tuber-soil were 0.728 and 0.44, respectively. The static friction coefficients of Corydalis tuber-Q235 steel and Corydalis tuber-soil were 0.41 and 0.76, respectively, while the rolling friction coefficients were 0.02 and 0.033, respectively. Under these conditions, the relative error between the simulation tests and physical tests was minimized. This study provides particle models and calibrated simulation contact parameters for mechanical processing tasks such as sowing, harvesting, and drying of Corydalis tuber.

Abstract in Chinese

针对延胡索在种植、收获、加工等环节中缺乏与机械、土壤接触参数的现状，本研究结合仿真试验与物理试验对延胡索进行离散元仿真参数标定。借用三维扫描技术获得延胡索的三维轮廓模型，采用自动填充法建立延胡索的多球粘结颗粒模型。分别以延胡索与Q235钢、土壤的碰撞恢复系数，静摩擦因数及滚动摩擦因数为自变量，以碰撞高度、摩擦倾角及滚动距离为因变量进行仿真试验，并进行二次多项式拟合。将实际试验值带入二次多项式，获得延胡索与Q235钢、土壤的接触参数仿真值，并与实际试验值进行校对。试验结果表明：延胡索-Q235钢，延胡索-土壤的碰撞恢复系数分别为0.728、0.44；延胡索-Q235钢，延胡索-土壤的静摩擦因数分别为0.41、0.76；延胡索-Q235钢，延胡索-土壤的碰撞恢复系数分别为0.02、0.033时，仿真试验与实际试验相对误差最小。本研究可为延胡索播种、收获及烘干等机械加工提供颗粒模型与仿真接触参数。