Authors

Abstract

Discrete Element Method was used to study the fertilizer guiding mechanism of double-row orchard ditching fertilizer to solve certain problems, such as the low uniformity of fertilization in orchard. Firstly, on the basis of studying the existing B fertilizer guiding mechanism, A and C fertilizer guiding mechanisms were proposed, and three virtual simulation models of the fertilizer guiding mechanism were established. Secondly, the physical parameters of the fertilizer particles were analysed, combined with the dynamic analysis of the falling process of the fertilizer particles, the dynamic model of the fertilizer particles in the three fertilizer guiding mechanisms was established. Finally, three kinds of fertilizer guiding mechanisms A, B and C were analyzed by the discrete element simulation experiment, and the C fertilizer guiding mechanism was the best. Then, the C fertilizer guiding mechanisms under different curvature radius were simulated, the discrete coefficients of the edge region and the middle region were used to evaluate the fertilizer uniformity, and the optimal curvature radius of the C fertilizer guiding mechanism was obtained. The results of simulation and prototype orchard experiments show that the dispersion coefficients of the edge region and the middle region of the C fertilizer guiding mechanism are the smallest, the uniformity of fertilization is the highest, the A fertilizer guiding mechanism is the second, the B fertilizer guiding mechanism is the lowest; in the C fertilizer guiding mechanism under different radius of curvature, when the radius of curvature is 600mm, the dispersion coefficients of the edge region and the middle region of the C fertilizer guiding mechanism are the smallest, and the fertilization uniformity is the highest; after the optimization, the discrete coefficient is reduced from 0.51 to 0.26, and the fertilization uniformity is increased by 49.02%. This study has significant potential to design and processing of orchard ditching fertilizer applicator.

Abstract in Chinese

针对果园开沟施肥不均匀的问题，采用离散元仿真设计对果园开沟施肥机的导肥机构进行优化。首先，在研究现有B型导肥机构基础上，提出A型和C型导肥机构，建立三种导肥机构的虚拟仿真模型。其次，分析肥料颗粒的物理参数，结合肥料颗粒下落过程中的动力学分析，建立肥料颗粒在三种导肥机构中的动力学模型。最后，先对A型、B型、C型三种导肥机构进行离散元仿真试验，分析优化出最佳C型导肥机构；后对不同曲率半径下的C型导肥机构进行施肥均匀度仿真试验，利用边缘区域与中间区域的变异系数评价施肥均匀度，分析优化出C型导肥机构的最佳曲率半径。仿真与样机果园试验结果表明：C型导肥机构边缘区域与中间区域离散系数最小，施肥均匀度最高，A型导肥机构次之，B型导肥机构最低；在不同曲率半径的C型导肥机构中，曲率半径为600mm时，C型导肥机构边缘区域与中间区域离散系数最小，施肥均匀度最高；优化后变异系数由0.51减小到0.26，施肥均匀度提高49.02%。为果园开沟施肥机设计加工提供科学依据。