| Seeding opener is one of the core components of no-till planter, which performances can directly affect formation of seed furrow and location of buried seeds. Moreover, it has a very significant influence on the growth of germinating seeds. No-tillage sowing needs to minimize soil disturbance in order to prevent damage to soil structure and not to cause greater loss of moisture. Therefore, it has a big significance on the study of no-till planter opener working process and the situation of soil disturbance.This thesis regards an acute angle sowing no-tillage planter opener and topsoil of Heilongjiang Province as the research object, then successfully test and analysis physical and mechanical properties parameters of soil,and design three different soil into part of the opener. The method of discrete element has been used to carry on emulation analysis aiming at the working resistance while the opener operating and the situation of disturbance of the soil.Comparing the simulation results with laboratory soil bin test. The specific research contents as follows:(1) In order to obtain the physical and mechanical parameters of the soil, such as soil moisture content, density, internal friction coefficient, etc., the physical and mechanical properties of soil has been tested.(2) An opener is designed. According to the head of the swordfish streamlined curves, fitted curved opener was designed depending on the curve fitting principle, moreover, determine the structural parameters of the opener is determined, including buried angle of 30 °, buried clearance angle of 6 °, according to the fitting structural parameters of curved opener, designed linear and circular opener, opener and three kinds of three-dimensional modeling carried out.(3) These three kinds of openers is analyzed based on discrete element simulation. First, the establishment of contact mechanics model suitable for sticky soil particles, soil particles calibration parameters, including particle size and shape, par ticle density; secondly, identified three opener simulation program, and discrete element simulation; Finally, the opener by three working resistance and soil particles disturbances. Simulation results show that: the opener forward resistance between 21N~106N, vertical reaction force between 10N~35N,the width of the disturbance in the opener between 140mm~220mm, back in the soil between 17mm~80mm depth.(4) The experimental research of soil tank on three openers. Three test openers width of soil disturbance in the working resistance of different soil moisture and depth of the ditch and under each factor, back soil depth and other parameters. The results show: Three opener forward resistance between 26N~125N, vertical reaction force between 13N~42N, the widt h of the disturbance in the opener between 240mm~360mm, back in the soil depth of 13mm~79mm between.Based on the experimental results and simulation results are analyzed, trends come three kinds opener working resistance simulation and experimental result s are basically the same three opener working resistance with increasing soil moisture content increases, with ditching increasing depth increases, which in the opener opener depth 30 mm emulation error between 20% to 35%, trenching depth of simulation error when 60 mm between 14%-19%,ditching 90 mm depth of simulation error in time between 8% to 19%; by the opener of the three working resistance and analysis of soil disturbances compared curve fitting derived type opener of least resistance and its work the minimum width of the disturbance of soil particles, soil depth of the deepest back, indicating that the fitted curve type opener can be achieved on the feasibility of reducing the resistance and reduce the effects of soil disturbance, but also proved that t he discrete element analysis of soil openers in the process. |
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