种群空间分布状态对排种器吸种性能的影响  

Influence of seeds spatial distribution on suction performance of precision vacuum seeder

作　　者：赵湛[1] 李耀明[1] 陈进[2] 徐立章[1] 

机构地区：[1]江苏大学现代农业装备与技术部省共建教育部重点实验室,江苏镇江212013 [2]江苏大学机械工程学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2009年第6期559-563,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：高等学校博士学科点专项科研基金资助项目(20060299004);江苏大学现代农业装备与技术江苏省重点实验室开放基金资助项目(NZ200703)

摘　　要：建立了气吸振动式排种器充种过程中籽粒受力模型,采用标准k-ε湍流模型,运用CFD软件Fluent对籽粒在真实吸种气流场中的受力进行了计算.通过假设种群在振动种盘内呈正四面体空间分布,分析了种群层数n、压差Δp、籽粒间隙系数λ、吸种孔与籽粒直径比γ对籽粒受力的影响.结果表明:γ较小时,压差对籽粒受力的影响较小,γ较大时,籽粒受力的大小随压差的增加迅速增大;λ<1.25时,籽粒受力随λ的增加而迅速增大,λ>1.25时,增长趋势较为缓慢.结合离散元法模拟种盘内种子的运动规律,确定排种器的工作参数,并以油菜籽为对象,进行了排种器吸种性能试验.According to the force model of seeds during the suction process,the standard k-ε turbulence model was adopted and the force values on seeds in the real gas field nearby the vacuum nozzle of precision seeder were calculated using the CFD software Fluent. By assuming the seeds in the vibration tray are distributed with regular tetrahedron,the influence of seeds lay thickness,n,differential pressure,Δp,seeds gap coefficient,λ,and diameter ratio of nozzle and seed,γ,on the force values were analyzed. The calculation results indicate that with the increase of Δp,the force values increase quickly at large γ and slowly at small γ. With the increase of λ,the force values first increase rapidly for λ1.25 and then increase slower for λ1.25. Combined with the discrete element method（DEM） to simulate the seeds motion states under vibration plate,the optimum working parameters were obtained. The rape seeds were selected as materials and the experimental results show that the suction ratio is higher than 98%.

关 键 词：气吸式 精密排种器 种群空间分布 籽粒受力 CFD数值计算 

分 类 号：S223.2[农业科学—农业机械化工程]