PDF《驱导辅助充种气吸式精量排种器设计与试验》

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9 年5月农业机械学报第50 卷第5期doi:10.

6041 / j. issn. 1000鄄1298. 2019. 05.

007 驱导辅助充种气吸式精量排种器设计与试验 史摇 嵩摇 周纪磊摇 刘摇 虎摇 方会敏摇 荐世春摇 张荣芳 (山东省农业机械科学研究院, 济南 250010) 摘要: 针对现有气吸式排种器充种环节工作压力要求高、高速作业时充种性能不佳,导致排种质量下降的问题,采 用主动驱导种群、减少局部种间接触的方法,提高排种器高速条件下的充种率,并基于此设计了一种驱导辅助充种 气吸式精量排种器. 分析了排种器充种过程中种子的受力状态,阐述了排种盘导种槽辅助充种的工作原理,以及 在充种过程各阶段提高种子充填率的设计思路;

对导种槽外形曲线方程、斜面倾角进行了理论计算,确定了曲线的 基本参数;

利用气固耦合数值分析方法 CFD DEM,以型孔处局部空隙率为指标,进行了单因素仿真试验,确定了 导种槽曲线方程的基圆半径最优值. 为了验证设计结果,在工作压力 -

5、 -

6 kPa 条件下,分别与其他

2 种气吸式 排种器进行速度单因素对比试验,试验结果表明,所设计的排种器在高速条件下的漏充率优于其他排种器. 对所 设计的排种器进行了前进速度、工作压力的双因素试验,通过多目标优化方法,确定了排种器的最佳工作参数. 将 所设计的排种器安装在气力式玉米免耕播种机上,在3个工作速度下进行了单因素田间试验,结果表明,当作业速 度为 9郾11 km/ h 时,粒距合格指数为 95郾48% ,高速条件下充种性能较为稳定. 关键词: 精量排种器;

气固耦合;

试验;

驱导辅助充种 中图分类号: S223郾2+3文献标识码: A 文章编号: 1000鄄1298(2019)05鄄0061鄄10 收稿日期:

2019 03 03摇 修回日期:

2019 03

28 基金项目: 国家自然科学基金项目(51605268)、山东省自然科学基金项目(ZR2016EEB22)、山东省重点研发计划项目(2018GNC112001) 和山东省农业科学院农业科技创新工程项目(CXGC2018E18) 作者简介: 史嵩(1986―),男,工程师,博士,主要从事农业机械装备设计与理论研究,E鄄mail: shisongfox@ 163. com 通信作者: 荐世春(1963―),男,研究员,主要从事农业机械装备设计与理论研究,E鄄mail: jscsh2002@ 163. com Design and Experiment of Pneumatic Precision Seed鄄metering Device with Guided Assistant Seed鄄filling SHI Song摇ZHOU Jilei摇LIU Hu摇FANG Huimin摇JIAN Shichun摇ZHANG Rongfang (Shandong Academy of Agricultural Machinery Sciences, Ji蒺nan 250010, China) Abstract: Aiming to solve the problem of poor seeding quality of the current air鄄suction vertical disc precision seed metering device caused by higher demands for working pressure during seed鄄filling process at high speed working conditions. One kind of air suction precision seed metering device with guided assistant seed filling plate was designed to improve the singulation index (SI) of the seed meter at high speed. Basic parameters of the curve were expounded, the source of resistance during the seed鄄filling was analyzed, and the ideal filling state of the various segments of the seed was presented. An optimal value of the base circle radius of the disturbance groove curve equation was proposed by the calculation of disturbance trough curve equation, the calculation of edge tilt angle, and a single factor simulation experiment was carried out with the CFD DEM method by gas鄄solid coupling numerical analysis with local void ratio as an indicator. In order to verify the design results, an single factor simulation experiment which compared with two domestic popular air鄄suction vertical disc precision seed metering devices was carried out under the working wind pressure of - 5郾0kPa and - 6郾0kPa. The results showed that the missing rate and the qualified rate were better than those of the other two seed metering devices. Two鄄factor experiments of operation pressure and forward speed were made on the designed seed metering devices, the optimal operating parameters were proposed by multi鄄objective optimization analysis. The developed seed metering device was installed on the electrical drive air suction type seeding machine, and the single factor repeating factor test was carried out at three working speeds. When the working speed was 9郾11 km/ h, the grain distance qualified index was 95郾48% , and the seed鄄filling had a better performance at high speed conditions. Key words: precision seed鄄metering device;