Design And Experiment Of Potato Curved Surface Sowing Furrow Opener

Potatoes are one of the four staple foods.As a key part of the potato planter for ditching and sowing,the ditching performance directly affects the quality of potato sowing.The scoop-type potato planter is the most widely used potato planter,and its seeding device mostly uses a scoop-type double row seeder.With the development of potato planting mechanization,the operating efficiency of potato planters continues to increase,and the contradictions between the existing potato planting openers,such as large operating resistance,shallow soil return depth,and easy mixing of dry and wet soil,have intensified,which seriously affects the quality of seeding.Unable to achieve the desired operating results.In this paper,aiming at the problems of high resistance of potato seeding opener,shallow soil return depth,and easy mixing of dry and wet soil,combined with bionics design ideas and potato planting agronomic requirements,a kind of scoop-type double-row seed metering device is designed.The curved seeding opener is studied through simulation analysis,field experiment,parameter optimization and other methods and methods,in order to provide theoretical reference and technical support for the design of potato seeding opener.The main research content and conclusions are as follows:(1)Design of curved seeding openerReverse engineering technology is used to obtain the curve equation of the streamline curve of the yellowfin tuna mandible,and the original curve is reconstructed into a three-dimensional surface by the horizontal straight element method to form the overall structure of the ditching and soil-breaking surface.Based on the three-sided wedge theory,it is proved that the element line angle and the soil starting angle are one of the main influencing factors of the operation resistance of the ditch breaking soil surface and the soil slab.According to the agronomic requirements of potato planting depth,when the maximum ditching depth is 150 mm,the sliding cutting principle is used to determine that the maximum cutting edge angle is 132°,the working length of ditching and breaking soil surface is 272 mm,and the element line angle is 27°;The single factor test determined that the starting angle of the soil separating plate was 45°;by studying the relative displacement when the seed potato fell to the ground,it was determined that the upper side length of the upper retaining plate was 128 mm and the lower side length was 278 mm;The curved seeding opener performs finite element analysis to verify the strength and rigidity of the opener.(2)Performance test of curved seeding openerThe discrete element method was used to simulate the layering of dry and wet soil for verification tests,and the results showed that the curved seeding opener did not disturb the order of the soil layers;the operation of the curved seeding opener,the core type opener,and the shoe opener The resistance and soil return depth were compared in the field.The results showed that the average operating resistance of the curved seeding opener was higher than that of the core under the conditions of trenching depths of 100,125,150 mm and operating speeds of 3.6,5.4,and 7.2km/h.The opener and shoe opener were reduced by 18.3% and 33.4%,and the average soil return depth increased by 70.4% and 91.7% respectively.Field comparison of the seeding quality of the three openers showed that the curved seeding and trenching The linear deviation of the device is smaller than that of the core-type opener and the shoe opener,which meets the national standard.The lateral offset coefficient of the seed potato of the curved seeding opener is 9.5% and 10.1%less than that of the core-type opener and the shoe opener,respectively;the field comparison of the seed bed quality of the three openers shows that The soil moisture content in the seed furrow of the curved seeding opener is 3.5% and 4.7% higher than that of the core type opener and the shoe opener,respectively.The curved seeding opener can reduce the mixing of dry and wet soil.(3)Optimization test of working parameters of curved openerUsing discrete element software for parameter optimization,selecting trench depth and operating speed as test factors,operating resistance and soil return depth as evaluation indicators,a two-factor five-level quadratic regression orthogonal rotation center combination test was performed on the curved seeding opener.A regression model between trenching depth,operating speed and various evaluation indicators was established;the parameter optimization results showed that the best combination of parameters for the curved seeding opener was: when the trenching depth was 109.49～130.92 mm and the operating speed was 3.6～7.2 km/h,the operating resistance is 228.08～326.32 N and the soil return depth is 32.28～40.05 mm;the optimization results of the curved seeding opener are simulated and verified,and the results show that the evaluation indicators of the curved seeding opener are simulated The relative error between the measured value and the predicted value of the regression model is small,and the result of the optimization combination is highly credible;the field verification test of the curved seeding opener is carried out,and the results show that the simulated actual value of each evaluation index of the curved seeder is compared with the field measured value The relative error of is small,and the simulation optimization result is more reliable,which verifies the feasibility of simulation optimization.