辅助充种带气吸式蚕豆精量排种器设计与试验

Design and Experiment of Air-suction Broad Bean Seed Metering Device with Flat Belt Auxiliary Seed-filling

针对蚕豆种子粒径大、三轴尺寸差异大,充种困难的问题,设计了一种带有平带辅助充种装置的气吸式蚕豆精量排种器。通过对充种过程中的动力学分析阐述了平带辅助充种装置及种子的运动机理;利用计算流体力学和离散元法双向耦合模拟的方法(Computational fluid dynamics and discrete element method,CFD-DEM),开展了单因素试验,确定了影响排种器充种性能的主要零部件参数并明晰了平带辅助充种机理;搭建试验台架,选取作业速度、平带输入轴转速和负压为试验因素,合格指数、重播指数、漏播指数为试验指标,进行了二次回归正交组合试验。试验结果表明,影响排种器合格指数的因素主次顺序为:作业速度、负压、平带输入轴转速。对试验结果进行多目标优化,得到最优参数组合为作业速度5.69 km/h、平带输入轴转速395 r/min、负压3845 Pa,对此结果进行排种器性能试验验证,此时合格指数为91.6%、重播指数为3.8%、漏播指数为4.6%,满足蚕豆播种要求。

An air-suction metering device for broad beans with a flat belt auxiliary seed-filling device was designed to address the difficulties of sowing large-sized and highly different three-axis dimensional broad bean seeds.The motion mechanism of the flat belt auxiliary seed-filling device and seeds was elucidated through a dynamic analysis of the seed-filling process.A one-factor test was conducted by using the computational fluid dynamics and discrete element method bidirectional coupling simulation method(CFD-DEM)to determine the main component parameters affecting the seed-filling performance and clarify the mechanism of the flat belt auxiliary seed-filling device.An experimental platform was constructed,and a quadratic regression orthogonal combination test was conducted with operating speed,flat belt input shaft speed,and negative pressure as the test factors and qualified index,reseeding index,and miss-seeding index as the test indicators.The test results showed that the primary and secondary factors affecting the qualified index of the air-suction metering device were operating speed,negative pressure,and flat belt input shaft speed.A multi-objective optimization of the test results yielded the optimal parameter combination of the operating speed at 5.69km/h,flat belt input shaft speed at 395r/min,and negative pressure at 3845Pa.The air-suction metering device performance was verified through sowing tests with a qualified index of 91.6%,reseeding index of 3.8%,and miss-seeding index of 4.6%,which met the requirements for broad bean planting.