Authors

Abstract

To improve the seed-filling performance of pneumatic precision seed metering devices for small-seeded crops, a U-shaped seed agitation plate and a combined-type agitation plate were developed. The agitation performance of cylindrical, U-shaped, and combined-type agitation plates was evaluated using the average and maximum velocities of the seed population as quantitative indicators. A three-factor, three-level simulation experiment based on the Discrete Element Method (DEM) was conducted, with agitation plate type, rotational speed, and knob height as the main factors. The optimal parameter combinations were determined as follows: for millet, a combined-type agitation plate with a rotational speed of 24.85 r/min and a knob height of 8.36 mm; for broomcorn millet, 24.17 r/min and 7.96 mm; and for rapeseed, 22.93 r/min and 8.57 mm. Bench experiments were carried out to validate the optimized combined-type agitation plate. The seed-filling rates reached 99.3%, 100%, and 99.7% for millet, broomcorn millet, and rapeseed, respectively. The results indicate that the combined-type agitation plate significantly improves seed mobility and filling performance, providing an effective solution for precision seeding of small-seeded crops.

Abstract in Chinese

针对小籽粒气吸式排种器搅种效果不佳而使得排种盘充种效果差的问题，本研究设计了一种U型搅种钮和组合型搅种钮。为了对比和验证圆柱型、U型、组合型三种搅种盘的搅种质量，以种群在搅种过程中的平均速度和最大速度为评价指标，选取搅种盘类型、搅种盘转速、搅种钮高度为试验因素利用EDEM离散元仿真软件对其进行了三因素三水平正交仿真试验，得到了谷子最佳参数组合为组合型搅种盘、作业速度24.85r/min、搅种钮高度8.36 mm，糜子最佳参数组合为组合型搅种盘、作业速度24.17 r/min、搅种钮高度7.96mm，油菜籽最佳参数组合为组合型搅种盘、作业速度22.93 r/min、搅种钮高度8.57 mm。通过台架试验对谷子，糜子，油菜籽种群搅种钮高度分别为8.4 mm、8.0 mm、8.6 mm时在最低工作速度10r/min时的搅种效果进行验证，组合型搅种盘对应三类种子的充种率分别为99.3%、100%和99.7%，优于圆柱形和U型搅种盘。试验证明组合型搅种盘具有良好的搅种效果，能够满足小籽粒种子的搅种需求。