摘要
针对当前预切种式木薯播种器存在充种效果差、合格指数低的问题,该研究设计了一种由落种滑板、主动辊筒、型孔摩擦带、支撑辊组、从动辊筒及储种箱等组成的预切种式木薯型孔摩擦带式精密排种机构。阐述了排种机构的基本结构和工作原理。对关键部件参数进行设计,通过理论分析确定影响排种机构充种性能的主要因素为型孔摩擦带型孔形状、型孔数量、型孔摩擦带安装倾角、型孔摩擦带速度以及种茎层厚度。基于离散元法(discrete element method,DEM)建立种茎群-型孔摩擦带仿真模型,通过单因素仿真分析各因素对充种性能及种茎群规律的影响。以充种合格指数和漏充指数为评价指标,通过二次回归正交旋转组合仿真分析确定最优参数,利用Design-Expert数据软件,建立各试验因素与评价指标的数学回归模型,并进行参数优化。结果表明,影响充种合格指数和漏充指数的因素主次顺序为型孔摩擦带速度、型孔摩擦带安装倾角和种茎层厚度,圆整后的最优参数为型孔摩擦带速度0.6 m/s、型孔摩擦带安装倾角45°,种茎层厚度250 mm,此时的模型预测充种合格指数为94.63%,漏充指数为3.42%,重充指数为1.95%。在最优参数下进行台架试验验证,种茎层厚度为220~280 mm,型孔摩擦带速度0.6 m/s,型孔摩擦带安装倾角45°,C型孔和型孔数12条件下,充种合格指数为94.13%,漏充指数为3.77%,验证试验结果与模型预测值相对误差小于5%。所设计的排种机构作业效果优于现有槽轮式排种机构,品种适应性良好,符合木薯精密播种的农艺要求。研究结果可为木薯精密播种器研制提供参考。
Cassava cultivation is low-cost and high-yielding,and tubers,stems and leaves can be widely utilized in the food medicine and light industry.However,cassava planting is mainly manual work at present.There is an urgent need to develop precision planting machines suitable for the agronomic requirements of cassava planting.A seeder is the core component of a precision planting machine,including the real-time and pre-cut seed-cutting type.Among them,the real-time seed cutting cannot realize the automatic sowing,due to the long and complicated shape of the cassava seed rods,while the low persistence of manual seed feeding and serious leakage.A seed cutter can be used to cut the cassava seed stems into seed stems of about 150 mm in length in pre-cut seeding.An automatic continuous and controlled seeding of cassava seed stems can be achieved through the seed discharge mechanism after cleaning.The lifting type seed rower has been improved to add the gravity seed cleaning mechanism,while the structure of the clamping plate has been optimized for the seed rowing effect.But the leakage filling still exists so far.Some research has been conducted on the seeders,such as slotted wheels,and single roller types.However,it is very necessary to improve the seed filling performance and qualification index,when seeding cassava seed stems with the existing pre-cut seed sower,because the cassava seed stems are cylindrical woody stalks of a certain length with surfaces of complex physical characteristics.Particularly,the performance of cassava precision seeding needs to be improved,due to a complex process with the multi-factor change.This study aims to improve the seed filling effect and low qualification index of pre-cut seeding type cassava precision seeder.A precision cassava seeding mechanism was designed with pre-cut seeding and friction belt,consisting of seed drop slide,active roller,type hole friction belt,support roller group,driven roller,and seed storage box.The basic structure and working principle of the seed-rowing mecha
作者
陈林涛
刘兆祥
牟向伟
于新业
李开文
马旭
刘建军
CHEN Lintao;LIU Zhaoxiang;MOU Xiangwei;YU Xinye;LI Kaiwen;MA Xu;LIU Jianjun(Department of Mechanical Engineering,Guangxi Normal University,Guilin 541004,China;College of Engineering,South China Agricultural University,Guangzhou 510642,China;Doris Woodworking Machinery Co.,Ltd.,Guilin 541004,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2023年第13期55-67,共13页
Transactions of the Chinese Society of Agricultural Engineering
基金
广西高校中青年教师基础能力提升项目(2022KY0058)
桂林市创新平台和人才计划项目(20210217-7)
广西重点研发计划项目(2021AB38023)
广西自然科学基金项目(2018GXNSFAA050026)。
关键词
农业机械
离散元法
木薯
排种机构
型孔摩擦带
种茎层厚度
agricultural machinery
discrete element method
cassava
seeding mechanism
shaped hole friction belt
seed stem layer thickness
