【摘要】 为解决利用离散元法对艾草机械化收割、脱叶和切碎等关键作业环节进行仿真分析时缺乏准确模型的问题，采用物理试验与仿真试验相结合的方法，以成熟期新鲜艾草茎秆为研究对象，基于EDEM仿真软件中的Hertz—Mindlin(no slip)模型和Hertz—Mindlin with bonding模型对茎秆物理参数和黏结参数进行标定。通过Plackett—Burman试验、最陡爬坡试验和Central—Composite试验确定艾草茎秆接触参数和黏结参数，并利用艾草茎秆堆积角台架试验和剪切物理试验验证参数值的准确性。结果表明：艾草茎秆间的碰撞恢复系数、静摩擦因数和动摩擦因数分别为0.13、1.09和0.026；艾草茎秆与作业装备间的碰撞恢复系数、静摩擦因数和动摩擦因数分别为0.43、0.73和0.015 6；艾草茎秆法向接触刚度、切向接触刚度、临界法向应力和临界切向应力分别为3.91×10~9 N/m、2.43×10~9 N/m、4.35×10~6 Pa和6.14×10~6 Pa；堆积角台架试验和剪切物理试验验证出的相对误差分别为0.96%、2.89%，误差较小。艾草茎秆离散元模型及标定的仿真参数准确可靠，能够真实反映其物理和力学特性，为艾草茎秆离散元仿真研究提供参考。更多还原

【Abstract】 In order to address the lack of accurate models for simulating key operational processes, such as mechanized harvesting, defoliation and chopping, of Artemisia argyi using the discrete element method(DEM), this study adopted a combination of physical experiments and simulation analyses. Mature fresh Artemisia argyi stalks were used as the research object. The physical and bonding parameters of the stalks were calibrated using the Hertz—Mindlin(no slip) model and Hertz—Mindlin with bonding model within the EDEM simulation software. To determine the contact and bonding parameters of the Artemisia argyi stalk, a series of experimental designs was employed, including the Plackett—Burman test, the steepest climb test, and the Central—Composite design. The accuracy of the calibrated parameters was verified through a stacking angle bench test and a shear test conducted on the stalks. The results showed that the collision recovery coefficient, static friction coefficient, and kinetic friction coefficient between Artemisia argyi stalks were 0. 13, 1. 09 and 0. 026 respectively. Between the stalks and operating equipment, the corresponding values were 0. 43, 0. 73 and 0. 015 6 respectively. The normal contact stiffness, tangential contact stiffness, critical normal stress, and critical tangential stress of the stalks were 3. 91×10~9 N/m, 2. 43×10~9 N/m, 4. 35×10~6 Pa and 6. 14×10~6 Pa, respectively. The relative errors for the stacking angle and shear tests were 0. 96% and 2. 89% respectively, indicating high accuracy. The discrete element model and the calibrated simulation parameters of the Artemisia argyi stalks proved to be both accurate and reliable, effectively capturing their physical and mechanical characteristics. These findings provide a robust reference for future DEM-based simulation studies involving Artemisia argyi.更多还原