摘要
铲片是树木移植机的重要工作部件,其尺寸参数、形状以及数量分布决定着移植机的挖土性能和整机的能耗大小。为了有效减小铲片切削土壤时所受阻力、减小整机能耗,该文根据树木移植机的工作状况和特点,对铲片进受力分析并建立力学模型。仿照土壤动物步甲的掘土器官大颚的体表结构设计非光滑仿生铲片,运用动力学分析软件ANSYS/LS-DYNA对原型铲片和仿生铲片切削土壤过程进行数值优化,通过原型铲片的数值仿真确定最佳铲片切削角为83?,在相同的铲片结构和土壤条件下,数值优化得到仿生铲片最佳参数为表面凸起直径14 mm,凸起中心距28 mm,凸起高度4 mm。根据最佳参数研制仿生铲片,并安装在移树机上进行原型铲片和仿生铲片的作业对比试验,发现仿生铲片有效减阻11.11%,证明了仿生非光滑铲片具有较好的减阻特性,可为整机节能降耗奠定基础。
Transplanting trees is a high intensity work,which is necessary to be mechanized in modern society.At present,most of the tree transplantation machines are developed on the basis of general excavators,which have the disadvantages of high power requirement and high energy consumption.Its performance can be improved in 2 aspects,which are the power matching of the whole machine and the resistance reduction during digging process.The commonly used tree transplantation machines in the market dig holes with a shovel.The shovel is an important part of the machine.The machine’s digging performance and the energy consumption are determined by the size,shape and quantity of shovel.In order to reduce the resistance of the shovel,scholars have carried out a series of researches on bionic structural and surface.It is noticed that some animals living in soil for a long time have the characteristics such as geometric non-smooth units on the surface of theirs body,which is the main reasons for reducing the viscosity and resistance,and the soil animal-ground beetle is a typical representative of this feature.In order to reduce the resistance and the energy consumption effectively when digging soil,the paper analyzed the force of the shovel and established the mechanical model according to the working conditions and characteristics.Solidworks and ANSYS/LS-DYNA software were used to establish the numerical model of the shovel and soil,digging process was simulated in software and the force of the shovel was calculated.Through numerical simulation,the digging angle of the shovel was optimized;it was found that the optimal digging angle of the shovel is 83°.Then,a new type of bionic shovel was designed to simulate the surface structure of the soil organ of soil animal-ground beetle,there were many convex units with the shape of sphere on the surface of the shovel,and the size,shape and distribution of the convex units is main considered.Under the condition that the digging angle of the shovel is 83°,the best parameters of the bionic shovel were obtained by numerical optimization:the convex diameter is 14 mm,the center distance of the convex is 28 mm,and the height of the convex is 4 mm.The bionic shovel was developed according to the best parameters and was installed on the prototype of the tree transplant machine to carry out the comparison test.Because the shovel is operating inside the soil,it is impossible to accurately measure the force by sticking the strain gauge on the surface of the shovel,so the hydraulic cylinder pressure of the driving was tested to reflect the force of the shovel indirectly,that is,the force of shovel was equal to the inlet pressure multiply with the inlet area of hydraulic cylinder.5 times experiment were carried,and the maximum and average force of shovel were recorded:The maximum force of bionic shovel was 2.474 kN,compared with 2.783 kN of the original shovel,the force was reduced by 0.309 kN,the average force reduced 0.512 kN.The results showed that the bionic shovel can effectively reduce the resistance of 11.11%.The bionic shovel is proved to have a good resistance reduction characteristic,which can provide technical support for energy-saving and consumption reduction of the tree transplant machine.
作者
赵雄
马行潇
高巧玲
陈成锦
陈建能
Zhao Xiong;Ma Xingxiao;Gao Qiaoling;Chen Chengjin;Chen Jianneng(Faculty of Mechanical Engineering&Automation,Zhejiang Sci-Tech University,Hangzhou 310018,China;Zhejiang Safun Industrial Co.,Ltd.,Jinhua 321300,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2018年第16期37-42,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
浙江省重大科技专项重点农业项目(2015C02004)
国家自然科学基金项目(51775512
51675486)
浙江理工大学"521"人才培养计划项目
关键词
仿生
设计
试验
减阻铲片
树木移植
bionics
design
experiments
resistance reducing shovels
tree transplantation
作者简介
赵雄,男,副教授,博士,主要从事农业机械装备与技术方面的研究。Email:zhaoxiong@zstu.edu.cn。;通讯作者:陈建能,男,教授,博士,主要从事农业机械装备与技术方面的研究。Email:jiannengchen@zstu.edu.cn。
