牧草免耕播种机滑刃式倒T型开沟器设计与试验

Design and Testing of Sliding-edge Inverted T-shaped Opener for No-tillage Seeder of Forage Crops

摘要:

针对牧草免耕播种机开沟器存在播种深度不均匀、土壤回填过多等问题,结合滑切作用原理,设计一种牧草 免耕播种机滑刃式倒T型开沟器。基于质点动力学分析土壤与开沟器之间的相互作用,确定影响其作业性能的主要因素,结合沙蟒头部轮廓对倒T型成形块进行仿生设计,仿真对比结果表明,仿生成形块所产生的土壤颗粒流速与楔式成形块相比提高5.48%,作业阻力减少15.88%。建立EDEM仿真模型并以作业速度、滑切角度、上倾角度为试验因素,回土深度、开沟深度稳定系数为试验指标,开展二次回归正交旋转组合试验,通过Design-Expert 软件 对二次回归正交旋转组合试验的结果进行分析,确定开沟器最优参数组合为:滑切角度40.24°、作业速度7.60km/h、上倾角度12.43°,此时开沟深度稳定系数为88.64%、回土深度为19.43mm。土槽试验表明,最优参数组合下开沟深度稳定系数为87.21%、开沟器平均回土深度为22.00mm,仿生成形块的作业阻力低于楔形成形块,平均降阻幅度为8.66%。田间试验结果表明,在作业速度6~10km/h范围内,滑刃式倒T 型开沟器开沟深度稳定系数均高于80.86%,回土深度均小于26.00mm,在草原土壤环境中具有良好的开沟性能。

Abstract:

Aiming at the problems of uneven seeding depth and excessive soil backfilling of the no-till grass seeder opener,a sliding blade type inverted T-shaped opener for no-till grass seeder was designed based on the principle of sliding cutting. The interaction between soil and the opener was analyzed based on particle dynamics, and the main factors affecting its working performance were determined. The inverted T-shaped forming block was designed based on the sand boa. The simulation results showed that the soil particle flow rate generated by the bionic forming block was 5.48% higher than that of the wedge-shaped forming block,and the working resistance was reduced by 15.88% . An EDEM simulation model was established,and the working speed,sliding cutting angle,and upper inclination angle were taken as the test factors,while the backfilling depth and the stability coefficient of the furrow depth were taken as the test indicators. A quadratic regression orthogonal rotation combination test was carried out. The optimal parameter combination of the opener was determined as: sliding cutting angle of 40.24°,working speed of 7.60 km/h,and upper inclination angle of 12.43°. At this time,the stability coefficient of the furrow depth was 88.64% and the backfilling depth was 19.43 mm. The soil trough test showed that the stability coefficient of the furrow depth was 87.21% and the average backfilling depth of the opener under the optimal parameter combination was 22.00 mm. The working resistance of the bionic forming block was lower than that of the wedge-shaped forming block,with an average resistance reduction of 8.66%. The field test results showed that within the working speed range of 6~10km/h, the stability coefficient of the furrow depth of the inverted T-shaped opener was higher than 80.86% ,and the backfilling depth was less than 26.00mm,indicating good furrow opening performance in grassland.