基于切抛土运动特性的小麦双轴分层旋耕装置设计与试验

Design and Experiment of Wheat Double-axis Layered Rotary Tilling Device Based on Soil Cutting and Throwing Motion Characteristics

摘要:

双轴旋耕切抛土过程与双轴配置参数关系决定土壤扰动程度与粒径分布,直接影响地表平整度和碎土能力。本文分析了双轴旋耕运动规律及抛土性能,建立了前后旋耕刀组将土壤颗粒向后抛撒的最大水平距离和高度方程,确定了影响双轴分层旋耕覆土装置工作性能的主要因素为前旋耕刀轴回转半径、后旋耕刀轴回转半径、前后旋耕刀轴水平间距和前后旋耕刀轴垂直间距。运用离散元法模拟双轴分层旋耕作业过程,以功耗、碎土率、回填率为试验指标,以前旋耕刀轴回转半径、后旋耕刀轴回转半径、前后旋耕刀轴水平间距和前后旋耕刀轴垂直间距为试验因素,进行了单因素和正交试验,建立了功耗、碎土率、回填率回归方程。利用Design-Expert 分析软件得到最优参数组合为:前旋耕刀轴回转半径268.95mm,后旋耕刀轴回转半径244.51mm,前后旋耕刀轴水平间距546.04mm,前后旋耕刀轴垂直间距54.31mm,此时仿真功耗为12.2kW、碎土率为97.3%、回填率为94.0%。在最优参数组合下进行田间试验,结果表明:当前旋耕刀轴回转半径为269mm,后旋耕刀轴回转半径为245mm,前后旋耕刀轴水平间距为546mm,前后旋耕刀轴垂直间距为54mm时,碎土率为96.8%,耕后地表平整度为2.4cm,整体耕整效果优于常用机型。

Abstract:

The process of double-axis rotary tillage and soil throwing and the relationship between the parameters of the double-axis configuration determine the degree of soil disturbance and the particle size distribution, directly affecting the surface flatness and the ability to break up the soil. The movement law of the double-axis rotary tillage and the discarding performance were analyzed, the equation for the maximum horizontal distance and height at which the soil particles were thrown backward by the front and rear tillage knife groups was established. It determined that the main factors affecting the working performance of the double-axis layered rotary tillage and soil covering device were the rotation radius of the front rotary tillage knife shaft, the rotation radius of the rear rotary tillage knife shaft, the horizontal spacing between the front and rear rotary tillage knife shafts, and the vertical spacing between the front and rear rotary tillage knife shafts. The double-axis layered rotary tillage operation process was simulated by using the discrete element method. The test indicators were power consumption, soil fragmentation rate, and backfill rate. The single-factor and orthogonal experiments were conducted by using the rotation radius of the front rotary tillage knife shaft, the rotation radius of the rear rotary tillage knife shaft, the horizontal spacing between the front and rear rotary tillage knife shafts, and the vertical spacing between the front and rear rotary tillage knife shafts as the test factors. Regression equations for power consumption, soil fragmentation rate, and backfill rate were established. The optimal parameter combination was obtained by using the Design-Expert analysis software: the rotation radius of the front rotary tillage knife shaft was 268.95mm, the rotation radius of the rear rotary tillage knife shaft was 244.51mm, the horizontal spacing between the front and rear rotary tillage knife shafts was 546.04mm, and the vertical spacing between the front and rear rotary tillage knife shafts was 54.31mm. In this case, the simulation power consumption was 12.2kW, the soil fragmentation rate was 97.3%, and the backfill rate was 94.0%. Field experiments were conducted under the optimal parameter combination. The results showed that when the rotation radius of the front rotary tillage knife shaft was 269mm, the rotation radius of the rear rotary tillage knife shaft was 245mm, the horizontal spacing between the front and rear rotary tillage knife shafts was 546mm, and the vertical spacing between the front and rear rotary tillage knife shafts was 54mm, the soil fragmentation rate was 96.8%, the surface flatness of the soil after tillage was 2.4cm, and the overall tillage effect was better than that of commonly used machines.