Design and Experiment of Corn Layer Fertilization Device with Fertilizer Flow Reconstruction Based on Discrete Element Method

： To enhance the accuracy of proportional fertilizer distribution for corn layered fertilization and the stability of soil coverage between layers, a layered fertilizer flow reconstruction apparatus was developed. The optimal diameter of the circular bulk fertilizer disc was determined to be 20 m m by using the discrete element method. Subsequently, a comparative test was carried out between fertilizer flow reconstruction and non-reconstruction. The results demonstrated that after fertilizer flow reconstruction, the operational efficiency was improved, and the stability of both 7: 3 and 8: 2 ratio fertilizers was enhanced. By conducting kinematic analysis of ditching for layered fertilization, it was established that the trencher's angle, the lateral distance of the shallow fertilizer opening, and the machine's operating speed were key factors influencing the efficacy of layered fertilization. A regression model was formulated to correlate the variation coefficient of each factor with the depth of deep and shallow fertilizers. The impact of the interaction of each factor on the test index was then analyzed by using the response surface method. By using the multi-objective optimization design method, the optimum operation parameter insertion angle of the layered fertilizer applicator was 390, the transverse spacing was 174 m m, and the operation speed was 4. 3 km/h. Based on the optimized parameters, the layered fertilization device was manufactured, and field tests were conducted. The results revealed that the variation coefficient of deep fertilizer depth was 4. 7 8 %, while that of shallow fertilizer was 6.41%. The stratified fertilization operation exhibited stability and reliability. The research result can offer a theoretical and methodological foundation for the design of layered fertilization devices. © 2024 Chinese Society of Agricultural Machinery. All rights reserved.