Authors

Abstract

This study addresses the challenges of poor contact parameter matching and the lack of systematic calibration methods in discrete element simulations of agricultural machinery, lateritic soil, and crops. Focusing on three interfaces—Panax notoginseng seedlings–lateritic soil, lateritic soil–lateritic soil, and lateritic soil–65Mn steel—key contact parameters (JKR surface energy, restitution, static friction, rolling friction) were calibrated using EDEM. Physical tests (angle of repose, mixture collapse, inclined plane rolling) were combined with orthogonal experiments and response surface methodology to establish correlation models between simulations and physical tests. Through variance analysis and multi-objective optimization, optimal parameter combinations were determined: for lateritic soil–lateritic soil, JKR surface energy of 5.302 J/m² and rolling friction of 0.287; for lateritic soil–Panax notoginseng, JKR surface energy of 4.101 J/m², static friction of 0.482, and rolling friction of 0.124; and for lateritic soil–65Mn steel, JKR surface energy of 3.806 J/m², static friction of 0.42, and rolling friction of 0.09. Validation showed relative errors below 7.5% across all tests, with model accuracy improved by over 30% compared to pre-calibration. Field experiments further confirmed model stability and reliability. The findings support structural optimization and operational parameter matching for agricultural machinery and provide a reference for calibrating multiphase discrete element models in agricultural engineering.

Abstract in Chinese

针对当前农机具-红土-作物互作离散元仿真中多介质接触参数匹配性差、模型构建缺乏系统标定方法的问题，本文以三七种苗-红土、红土-红土及红土-65Mn钢三种核心接触界面为研究对象，开展基于EDEM的关键接触参数标定与优化研究。选取JKR表面能、碰撞恢复系数、静摩擦系数和动摩擦系数作为标定参数，综合堆积角试验、混合物坍塌试验及斜面滚动试验等物理测试方法，结合离散元仿真正交试验设计与响应面法，构建仿真结果与物理试验之间的相关性模型。通过方差分析与多目标优化算法进行参数筛选与迭代寻优，确定各接触界面的显著性参数及其最优组合：红土-红土的JKR表面能为5.302 J/m²、动摩擦系数为0.287；红土-三七的JKR表面能为4.101 J/m²、静摩擦系数为0.482、动摩擦系数为0.124；红土-65Mn钢的JKR表面能为3.806 J/m²、静摩擦系数为0.42、动摩擦系数为0.09；非显著性参数采用物理试验平均值进行设定。验证结果表明，基于最优参数组合构建的离散元模型在堆积角、混合物坍塌角及斜面滚动试验中的仿真结果与物理试验值的相对误差均小于7.5%，模型预测精度较标定前提升30%以上。结合田间试验与工况仿真进一步验证，该模型具有良好的稳定性与可靠性，有效解决了多介质接触参数匹配难题。研究成果为三七移栽机等农机具的结构优化与作业参数匹配提供了理论依据与技术支撑，也为农业工程领域多相介质离散元模型的参数标定提供了可借鉴的方法路径。