菱角离散元粘结参数标定与剪切试验  

Calibration and shear experiments of discrete element bonding parameters for water caltrop

作　　者：涂鸣[1] 曹涛 万志华 莫泓滔 张国忠[1] TU Ming;CAO Tao;WAN Zhihua;MO Hongtao;ZHANG Guozhong(College of Engineering,Huazhong Agricultural University/Key Laboratory of Agricultural Equipment in Mid-Lower Yangtze River,Ministry of Agriculture and Rural Affair,Wuhan 430070,China;School of Mechanical Engineering,Wuhan Polytechnic University,Wuhan 430023,China)

机构地区：[1]华中农业大学工学院/农业农村部长江中下游农业装备重点实验室,武汉430070 [2]武汉轻工大学机械工程学院,武汉430023

出　　处：《华中农业大学学报》2023年第4期270-278,共9页Journal of Huazhong Agricultural University

基　　金：国家特色蔬菜产业技术体系专项(CARS-24-D-02);湖北省高等学校优秀中青年科技创新团队计划项目(T201934)。

摘　　要：针对菱角(Trapa bispinosa Roxb.)脱壳初加工装备设计与仿真分析时缺乏有效的离散元模型问题,开展菱角粘结离散元参数标定与样机试验工作。采用三维反求技术获取菱角轮廓模型,测取菱角本征参数及基本接触参数,得到菱角平均剪切力为352.95 N,并以此为标定目标,采用EDEM软件中的Hertz-Mindlin with bonding模型建立菱角离散元模型,通过单因素试验筛选粘结参数标定范围,由二水平析因试验、最陡爬坡试验筛选显著因素及其标定区间,设计响应面试验求解粘结参数,确定离散元模型中的最优粘结参数组合,开展旋转剪切仿真试验及样机验证试验。结果显示:仿真得到的菱角脱壳剪切力为352 N,与实际误差为0.269%;菱角剪切刀具为矩形,转速230 r/min时,剪切力最小值为93.20 N,与预测值92.99 N的误差为0.215%;样机试验中矩形刀具在转速为230 r/min时各项性能指标最优,表明建立的菱角离散元模型可靠。To address the problem of the lack of effective discrete element models in the design and simulation analysis of water caltrop dehulling primary processing equipment,this paper carries out the research work of water caltrop discrete element parameter calibration and prototype test.The 3D inverse technique was used to obtain the water caltrop profile model,and the water caltrop intrinsic parameters and basic contact parameters were measured by physical tests.The average shearing force of the water caltrop was obtained from the uniaxial compression test as 352.95 N,and this was used as the calibration target.Based on the Hertz-Mindlin with bonding model,a water caltrop discrete element model was established to carry out virtual calibration tests on bonding parameters,and the calibration range of each parameter was initially screened by single-factor tests.The two-level analysis factor test and the steepest climb test were used to quickly screen the significant factors and their calibration intervals,and the Central composite response surface test was designed to solve the bonding parameters to determine the optimal combination of parameters in the discrete element model,and a rotary shear water caltrop simulation model was established to study the effects of different tools on water caltrop shear at different rotational speeds,which was used as a basis to design a shear vibration-type water caltrop sheller to carry out prototype tests to verify the reliability of the model.The results show that,the significant effect on the shearing force of the factor normal stiffness per unit area is 4.818×10^(7) N/m^(3),shear stiffness per unit area is 5.343×10^(8) N/m^(3),the remaining insignificant factors are taken as the middle level,that is,the normal stress per unit area is 1×10^(7) Pa,shear stress per unit area is 1×10^(7) Pa,bond radius of 1.6 mm.The shearing force of the simulated test is 352 N,with an error of 0.269%;the minimum shearing force of the rectangular tool screened from the rotary shear test is 93.20 N a

关 键 词：菱角 离散元 粘结参数 标定 剪切 仿真试验 

分 类 号：S226.4[农业科学—农业机械化工程]