Design And Numerical Simulation Of Gap Cutting Coulter For No-till Planter

Conservation tillage mainly covers the surface of crop stubble,which requires high sowing machine for crop sowing operation.Otherwise,blockage will occur,which will affect the quality of crop sowing and crop yield seriously.Aiming at the problem of difficult seeding in conservation tillage,the anti-blocking technology of no-tillage planter in Northeast China was studied.A notched disc cutter was designed.Static analysis of notched disc cutter was carried out,and discrete element analysis was carried out at the same time.Taking the working parameters as the research object,the optimal working performance was obtained to improve the operation performance of no-tillage planter in conservation tillage.The main research contents and conclusions are as follows:1)Structural design of notched disc cutter is carried out.According to the principle of increasing stubble cutting capacity,cutting straw and reducing soil disturbance,a new notched disc cutter was designed and its structural parameters were determined.2)Measure the physical parameters of soil under the common working environment of disc knife,including soil moisture content,soil bulk density and average soil solidity.The discrete element model of soil particles and the parameters of the ditcher were established.3)The static analysis of the new notched disc cutter is carried out by ANSYS Workbench.A three-dimensional simulation model is established and meshed.The boundary conditions(constraints and loads)are applied to obtain the static analysis results: the maximum stress is 31 MPa and the minimum stress is 219.3 Pa.The two values are far less than the yield limit value of65 Mn for the notched disc cutter.Accurate,determine the structural strength of the new notched disc cutter to meet the design requirements.4)Discrete element method is used to study the feasibility of working process of notched disc cutter.The suitable contact model between soil and disc cutter,and the appropriate Rayleigh time step is selected to study the working process of notched disc cutter when the working depth is 80 mm and the working speed is 4 km/h.5)The experimental study of notched disc cutter is carried out.Through the analysis of the factors affecting the performance of the disc cutter,the working speed and depth are determined as the test factors to study the influence of the working resistance test index;the mathematical model is obtained through the combined test;the test results are optimized by SPSS software,and the optimal working speed is 7 km/h and the work is determined by taking the minimum forwardresistance as the optimization objective.The depth is 80 mm.