The Tractive Notoginseng Harvester Design And Experimental Research

Currently,domestic research on the design theory and method of notoginseng harvester is still in the primary stage.Despite all the harvester of various short and long roots out of China,there is few researches and reports on harvesters that are suitable for the viscous red soil and notoginseng condition in Yunnan,China.Due to complicated manual harvesting process and a large number of factors that influence the working quality,it is challengeable leading edge topic to seek for a reasonable design theory of notoginseng harvester,on field experiment and parameter optimization method,to define the design theory of notoginseng harvester.In this paper,we take the Japanese ginseng(a kind of notoginseng)and viscous red soil(its viscosity and hardness are greatly influenced by water ratio of the soil)as main research objects to study the root tuber digging mechanism,separation mechanism of root tuber and soil,and loss pattern and mechanism of root tuber by establishing notoginseng root tuber digging model,separation mechanism of notoginseng root tuber and soil based on advanced research methods and skills.This paper,based on mechanics performance testing on notoginseng plants,systematically analyzed the mechanism of root tuber digging and separation of root tuber and soil and performed finite element modeling to actual digging process,to provide theoretical foundation for the design of notoginseng harvester.At the same time,based on the research and demonstration of notoginseng growing environment and artificial digging process,notoginseng harvester is designed and put into on field experiment.Main research contents,methods,and conclusions are as follows:1.This paper refers to the method in GB/T1040 "Measurement of Tensile Strength,Tensile Modulus,and Tensile Stress--Strain Relationship of Plastics and Composite Materials" and combines physical mechanical test to get the axial tensile strength of notoginseng stalks,Available:notoginseng root axial and radial elastic modulus were 27.80,21.07 Mpa.Notoginseng root poisson's ratio is 0.3,the outer skin of the axial and circumferential poisson's ratio were 0.12 and 0.04;Available:notoginseng root axial and radial elastic modulus were 27.80 Mpa,21.07 Mpa.Notoginseng root poisson's ratio is 0.3,the outer skin of the axial and circumferential poisson's ratio were 0.12 and 0.04;At the same time,notoginseng root tuber,central xylem,and external skin are common in anisotropic materials.2.Adopt SPH and ABAQUS/EXPLICIT algorithm to establish a 3D coupling calculation model of notoginseng digging process.Therefore,the difficulty in modeling and calculating soil deformation,rapture,and separation during digging notoginseng root tuber is solved.The simulation result shows that:During digging,the mixture of notoginseng and soil is gradually lifted with the upper cross-section of the digging shovel in the direction of the equipment.The soil kinks at the second stage cross-section of the shovel.The main reason why the joint surface of the soil and notoginseng is that:the shovel cuts,transforms,and compress the mixture,which leads to deformation and break of the mixture.3.Establish a monad model of notoginseng and soil.The data processing and calculating time are effectively reduced by simplifying the visualized simulation of root tuber digging and root-soil separation.At the same time,this paper explored the influence of different growing direction of notoginseng on digging process,and the influence of transfer lever vibration frequency,amplitude,spacing,and transfer rate on the transfer efficiency and separation effect.It is can be seen that the soil is protected to be complete,without any separation from the soil;The soil crushing mainly appears near the digging surface.The upper soil is cracked during tensile and cutting but not completely crushed;from the perspective of peak value,the vertical digging shows the largest strength,while horizontal digging shows the smallest.During transmission:the transmission efficiency is better when using lower frequency and higher amplitude;the separation efficiency is better when using higher frequency and higher amplitude;lower transmission speed can improve the transmission efficiency,with obtaining higher separation efficiency;larger spacing helps to improve the separation efficiency of notoginseng and soil.4.Verify the field physical performance of the designed equipment based on basic physical mechanical testing and finite simulation.Establish the largest digging resistance model of multiple factor coupling with the orthogonal experiment to obtain the largest digging resistance influence pattern of notoginseng.The better parameter model has guidance significance on the optimization of the mechanical digging process of notoginseng harvester.