Authors

Abstract

This study aimed to address the issues of poor conveying stability, seed damage, and high energy consumption in pneumatic seeders by systematically analyzing the impact of pipeline geometry on seed motion characteristics, integrating the coupled Computational Fluid Dynamics and Discrete Element Method (CFD-DEM) simulations with bench tests. The findings demonstrate that a 45 mm pipeline diameter provides the best overall conveying performance, decreasing system pressure loss by 18.8% relative to a 40 mm diameter and by 2.2% relative to a 50 mm diameter. A first straight section of 0.4 meters was found to provide the optimal balance between seed conveying velocity and collision protection during turns. The implementation of an arc-shaped turning structure with a 100 mm radius decreased the seed supply time to 9.48 seconds. This structure also demonstrated notably superior seed trajectory stability, improving by 26.2%, and enhanced flow field uniformity compared to polyline turn structures. This research gives important parametric guidance and theoretical support for the low-damage, high-efficiency design of pneumatic precision seeding systems.

Abstract in Chinese

本研究旨在通过系统分析管道几何形状对种子运动特性的影响，结合耦合计算流体动力学与离散元法（CFD-DEM）仿真与台架试验，解决气力式播种机存在的输送稳定性差、种子损伤大及能耗高的问题。研究结果表明，采用45毫米管径可获得最佳综合输送性能，与40毫米管径相比，系统压力损失降低了18.8%；与50毫米管径相比，降低了2.2%。首段0.4米直管段在种子输送速度与转弯处碰撞防护之间达到了最佳平衡。采用半径为100毫米的圆弧形转弯结构，将供种时间缩短至9.48秒。与折线形转弯结构相比，该结构在种子轨迹稳定性方面表现显著更优，提升了26.2%，并提高了流场均匀性。本研究为气力式精量播种系统的低损伤、高效率设计提供了重要的参数指导和理论支持。