基于离散元法的耕层残膜拉伸性能研究  

Tensile Properties of Residual Film in Tillage Layer Based on Discrete Element Method

作　　者：申世龙 张佳喜 蒋永新[3] 王毅超 刘旋峰[3] 李金明 董文浩 SHEN Shilong;ZHANG Jiaxi;JIANG Yongxin;WANG Yichao;LIU Xuanfeng;LI Jinming;DONG Wenhao(Mechanical and Electronic Engineering Institute,Xinjiang Agricultural University,Urumqi 830052,China;Xinjiang Key Laboratory of Intelligent Agriculture Equipment,Urumqi 830052,China;Institute of Agricultural Mechanization,Xinjiang Academy of Agricultural Sciences,Urumqi 830091,China)

机构地区：[1]新疆农业大学机电工程学院,乌鲁木齐830052 [2]新疆智能农业装备重点实验室,乌鲁木齐830052 [3]新疆农业科学院农业机械化研究所,乌鲁木齐830091

出　　处：《农业机械学报》2024年第7期132-141,共10页Transactions of the Chinese Society for Agricultural Machinery

基　　金：新疆农机研发制造推广应用一体化项目(YTHSD2022-09);新疆维吾尔自治区“揭榜挂帅”项目;新疆维吾尔自治区研究生科研创新项目(XJ2024G103)。

摘　　要：由于耕层残膜回收机关键农机部件设计优化过程中缺乏准确的残膜离散元模型参数,在一定程度上制约了耕层残膜回收机残膜受力机理分析与机构优化改进。本文以棉田耕层残膜为研究对象,对耕层残膜含量和极限拉伸力进行测定,得到不同耕层深度、不同厚度的残膜含量和极限拉伸力。根据测定结果,利用EDEM软件选用Hertz-Mindlin with Bonding接触模型对耕层残膜进行离散元模型参数标定,选用单位面积法向刚度、单位面积切向刚度、临界法向应力、临界切向应力、粘结半径、接触半径为试验因素。通过Plackett-Burman试验,确定影响Bond键的主要参数有单位面积法向刚度、临界法向应力和粘结半径。通过最陡爬坡试验和Box-Behnken试验,最终确定最优的Bonding模型显著参数单位面积法向刚度、临界法向应力、粘结半径分别为2.36×10^(5) N/m^(3)、6.47×10^(4) Pa、0.004 mm,对参数进行了仿真试验验证,误差为5.88%,满足要求。通过对比物理试验与仿真试验的拉伸过程耕层残膜状态与拉伸曲线,表明了耕层残膜模型合理性,为后期耕层残膜回收机仿真与膜土分离机理研究提供了理论支撑。Due to the lack of accurate discrete element model parameters in the design and optimization process of the key agricultural machinery components of the plough layer residual film recycling machine,the research on the interaction mechanism between the plough layer residual film recycling machine and the residual film was restricted to a certain extent.Taking the residual film in the tillage layer of cotton field as the research object,the residual film in the tillage layer content and ultimate tensile force were measured,and the residual film content and ultimate tensile force of different tilting depth and thickness were obtained.According to the measurement results,the Hertz-Mindlin with Bonding contact model was selected for discrete element model parameter calibration by using EDEM software.The normal stiffness per unit area,tangential stiffness per unit area,critical normal stress,critical tangential stress,bond radius and contact radius were selected as test factors.Through Plackett-Burman test,the steepest climbing test and Box-Behnken test were used in turn.Finally,the significant parameters of the optimal Bonding model were determined as normal stiffness per unit area,critical normal stress and bond radius,whose values were 2.36×10^(5) N/m^(3),6.47×10^(4) Pa and 0.004 mm,respectively.The simulation test was carried out to verify the parameters,and the error value was 5.88%,which met the requirements.Through the comparative analysis of the residual film in the tillage layer state and tensile curve of the physical testing and simulation test in the stretching process,the rationality of the residual film model in the tillage layer was proved,which provided theoretical support for the later residual film in the tillage layer recycling machine to simulate the mechanical recovery of residual film in the tillage layer and analyze the separation mechanism of film and soil.

关 键 词：棉田耕层残膜 极限拉伸力 离散元模型 Bonding模型 拉伸仿真试验 

分 类 号：S225.93[农业科学—农业机械化工程]