摘要
针对目前小麦种子尺寸小、形状不规则导致传统排种器存在漏充率高、充种合格率低等问题,设计了一种限制充种姿态-正负压式小麦精密排种器。排种器基于限制种子充种姿态的原理,增设弧形辅助充种板和搅种盘,使种子长轴与型孔长轴近似位于同一平面,在正负压良好充种的基础上获得更佳的单粒充种性能。通过对充种过程及种子田间分布情况的分析,计算确定排种器关键结构参数:型孔列数3列,每列型孔个数30个,型孔长度8 mm、宽度5 mm、深度3 mm;并采用EDEM软件进行仿真试验,确定了弧形辅助充种板的最优角度为5°。在此基础上,利用Design-Expert软件,以型孔轮转速、真空度、搅种盘转速为试验因素,以充种合格率、漏充率、重充率为评价指标,进行三因素三水平二次回归正交试验。通过构建回归方程及响应面数学模型,分析了各试验因素对排种器充种性能的影响,且对试验参数进行综合优化,确定最佳参数组合:型孔轮转速66.27 r/min、真空度3.52 kPa、搅种盘转速52.00 r/min,并进行试验验证,得到排种器充种合格率为92.70%,漏充率为3.47%,重充率为3.83%。该排种器满足小麦精密播种对排种器的性能要求。
Aiming at the problems that the irregular shape of wheat seeds leads to the high missing rate,low seed-filling qualified rate and difficult precision sowing of the traditional type hole wheel seed metering device under high-speed operation,a limited seed filling posture and combined type of positive and negative air pressure and wheat precision seed metering device was designed.The mechanical model of wheat seed was established by analyzing the movement and force of wheat seed during seed metering.The posture of seed filling was limited and the phenomenon of seed jamming was improved by adding arc-shaped auxiliary seed filling plate and seed stirring plate.The key structural parameters of the seed metering device were designed and calculated by analyzing the seed filling process and the distribution of seeds in the seed ditch,including the diameter of the type hole wheel was 100 mm,the length of the hole was 8 mm,the width of the hole was 5 mm,and the depth of the hole was 3 mm,etc.The optimum angle of arc-shaped auxiliary seed filling plate was determined to be 5°through the simulation analysis with EDEM software.On the basis of the above research,the quadratic orthogonal rotation combination test of three factors and three levels was carried out with the rotary speed of type hole wheel,the vacuum degree and the rotary speed of seed stirring plate as the test factors and the seed-filling qualified rate,and the missing rate and the multiple rate as the evaluation indexes.The regression equation between the evaluation index and the test factors was constructed,and the significance of the influence of each test factor on the index was analyzed.By optimizing the test parameters,the optimal parameter combination was obtained:the rotary speed of type hole wheel was 66.27 r/min,the vacuum degree was 3.52 kPa,and the rotary speed of seed stirring disk was 52.00 r/min.Under the conditions of above factors,the test verification was carried out,the seed-filling qualified rate was 92.70%,the missing rate was 3.47%,and the multiple rate was 3.83%.The experimental results showed that there was little difference between it and the optimization results,which showed that the seed metering device could meet the performance requirements of precision sowing for wheat.
作者
何瑞银
王建林
徐高明
贺鑫业
段庆飞
丁启朔
HE Ruiyin;WANG Jianlin;XU Gaoming;HE Xinye;DUAN Qingfei;DING Qishuo(College of Engineering,Nanjing Agricultural University,Nanjing 210031,China;Key Laboratory of Intelligent Agricultural Equipment of Jiangsu Province,Nanjing 210031,China)
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2022年第9期39-49,167,共12页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家重点研发计划项目(2016YFD0300908)
江苏现代农业产业关键技术创新项目(CX(19)2012)
关键词
小麦
排种器
正负压式
弧形辅助充种板
搅种盘
型孔轮
wheat
seed metering device
positive and negative pressure type
arc-shaped auxiliary seed filling plate
seed stirring plate
type hole wheel