Authors

Abstract

To improve the accuracy of numerical simulations of the rolling process of giant juncao stems using the discrete element method, this study focuses on the giant juncao stems. In conjunction with physical experiments on giant juncao stems stems and discrete element simulation methods, the Hertz-Mindlin with Bonding model is selected to establish a bonding model, and the parameters of the discrete element model are calibrated. The relative error between the numerical simulation's angle of repose and the angle of repose from physical experiments is used as an evaluation index. The Plackett-Burman test, Steepest Ascent test, and Box-Behnken test are designed to optimize the relevant parameters. The optimal parameter combination obtained includes a static friction coefficient between stems of 0.25, a rolling friction coefficient of 0.42, and a static friction coefficient between the stem and the steel plate of 0.52; the average angle of repose is 18.032°. Validation simulation tests are conducted with this parameter combination, resulting in a relative error of 1.1% between the obtained angle of repose and that from physical experiments. This indicates that the calibrated parameter results for the giant juncao stems can be used for discrete element numerical simulation of crushing studies.

Abstract in Chinese

为解决据巨菌草短茎埋栽种植时的排种技术需求，研究旨在设计符合巨菌草茎秆物理特性的排种器。本研究结合巨菌草茎秆物理试验和离散元仿真方法，选用Hertz-Mindlin with Bonding模型建立粘结模型，对离散元模型参数进行标定。将数值模拟休止角和物理试验休止角的相对误差作为评价指标，设计Plackett-Burman试验、Steepest Ascent试验和Box-Behnken试验对相关参数进行优化。获得最优参数组合：茎秆间静摩擦因数0.25、滚动摩擦因数0.42、茎秆与钢板静摩擦因数0.52；休止角平均值为18.032°。以此参数组合进行验证仿真试验，得到的休止角与物理试验休止角的相对误差为1.1%。以上表明，建立的巨菌草茎秆标定参数结果可用于离散元数值模拟粉碎仿真研究。