Design And Experiment Of Potato Trenching And Ridge Raising Device

Ridge tillage mode is one of the key links in potato production process,and has been widely used in Hubei and other regions because of its advantages of moisture conservation,irrigation and drainage,and root growth.With the popularization and popularization of potato ridge cultivation mode and the improvement of agronomic machinery integration,the operation quality of furrow and ridge machines has a significant impact on the yield and quality of potato.Due to abundant rainwater,heavy soil stickiness,large fluctuation of water content,insufficient ridge depth,irregular ridge type and poor stability in potato planting areas such as Hubei,a potato furrow and ridge device is designed in this paper to solve the problems of irregular and unstable ridge type of potato furrow and ridge machine in this area.The main contents of this paper are as follows:(1)Potato furrow and ridge device was designed.According to potato planting agronomic requirements in Hubei and other areas,the overall design scheme of furrowing and ridging device was determined and its working principle was elaborated in combination with the operating objects and working environment of furrowing and ridging device.The structure and parameters of guiding surface,wing and pressing plate of furrowing and ridging device are designed.The mechanical analysis of furrow and ridge opener was carried out and the mechanical model of traction resistance of each main contact component of furrow and ridge opener was established.(2)Contrast simulation tests of different types of guiding curves are carried out.The circular arc type,parabolic type,polynomial type,exponential type,power function type and Fourier type functions are selected as the guide curve types to establish the soil guiding surface.The simulation comparison tests of different types of furrow and ridging machines are carried out,and the relationship between the operation quality and traction resistance of various types of soil guiding surfaces is explored.In order to balance the ridging performance and drag reduction and consumption reduction,the guide curve of the guide soil surface is optimized and designed,and the type of guide curve is selected as a parabolic arc combined guide curve.The results show that the combined guide curve plow has a soil cultivation mass of 38.06 kg,a traction resistance of 3234.33 N,and a ridge height of 307 mm,meeting the agricultural requirements for planting in Hubei and other regions.(3)The simulation and comparison tests of different elevation angle variation laws of the conductive surface were carried out.The straight line type,ripe type and semi-helical type are selected as the change rule of element angle to establish the surface of soil guide,and simulation and comparison tests of different types of furrowing and ridging machines are carried out.The results show that the soil quality results are semi-helical plow body(38.03 kg)>straight plow body(37.76 kg)>ripe plow body(35.58 kg).The results of ridge height were semi-helical plow(308 mm)>straight plow(303 mm)>ripe plow(292 mm).The results of traction resistance were ripe plow(3358.20 N)>straight plow(3301.15N)>semi-helical plow(3250.62 N).According to the agronomic requirements of planting and the results of simulation and comparison,the semi-helical element angle variation law is selected to establish the surface of soil guide.(4)Multi-objective optimization design of furrow ridger was carried out.BBD center combination test is carried out with bulldozing angle,conduction curve opening and maximum element angle difference as test factors.Response surface analysis is carried out on the test results,and the influence trend of each factor interaction on traction resistance and soil quality is obtained.The mapping relationship between objective function and geometric parameters is obtained and the regression mathematical model is established.The multi-objective optimization model for global optimization is constructed and solved by genetic algorithm NSGA-II.The Pareto optimal solution set is ranked by using the method of Entropy Weighting-TOPSIS evaluation analysis.The optimum combination of structural parameters is bulldozing angle 35.67 °,conduction curve opening 198.91 mm and element line angle difference 12.00 °.The whole plant is simulated under three speed conditions,and the operation results of the whole plant meet the relevant agronomic requirements.(5)Field performance tests were carried out.The results showed that after operating at three speeds,the width range of the ditch bottom was 288.70 mm～31.30 mm,the height range of the ridge body was 286.50 mm～308.10 mm,and the distance between the ridges was 1152.80 mm～1192.70 mm.The stability coefficient of ditch width and ridge height at each operating speed were all above 90%,meeting the agricultural requirements for potato cultivation in Hubei and other regions;Under three speed conditions,the measured traction resistance in the experiment increased from 5480.09 N to 7364.02 N,and the simulated traction resistance increased from 4975.72 N to 6623.50 N.Both traction resistance increased with the increase of operating speed.The relative error range of traction resistance between the simulation results and the experimental results was8.00%～10.06%,and the simulation results showed the same trend of change as the experimental results,indicating that the discrete element simulation results have certain accuracy.