气吸振动式排种器吸种性能数值模拟与试验  

Numerical Simulation and Experiment on the Seeds Pickup Performance of Precision Air-suction Seeder

作　　者：李耀明[1] 赵湛[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省部共建教育部重点实验室 [2]江苏大学机械工程学院

出　　处：《农业机械学报》2008年第10期95-99,104,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：高等学校博士学科点专项科研基金资助项目(项目编号: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(项目编号:NZ200703)

摘　　要：建立了气吸振动式排种器吸种过程三维力学模型,基于Reynolds时均化的连续方程、Navier-Stokes方程和标准的k-ε湍流模型构成封闭方程组,并考虑真实气体的粘性和压缩性,运用CFD软件Fluent计算了籽粒在吸种口附近的受力,建立了力矩阵。采用二元线性插值法,通过计算吸孔的垂直吸种距离、径向吸种距离和有效吸种空间体积分析了排种器的吸种性能,绘制了籽粒吸种运动轨迹。分析了压差、吸孔直径对排种器吸种能力的影响。结果表明:增大吸孔直径和增加压差可以提高吸种性能,锥孔的吸种能力优于直孔和沉孔。以油菜籽粒为对象,通过性能试验得出了排种器的最佳工作参数。According to the working principles of the air-suction precision seeder, the 3 - D model of seeds pickup process was established. Take the compressibility and the viscosity of the real gas into account, the N - S equations and standard κ-ε turbulence model were applied to calculate the forces on seeds in the gas field nearby the vacuum nozzle by using the computational fluid dynamics （CFD） software Fluent. The axial pickup distance, the radial pickup distance, the volume of effective pickup region and the seeds pickup tracks were received through the binary linear interpolation method. The effects of the diameter of nozzles and the differential pressure on the pickup performance were analyzed, the results showed that the pickup performance of conical nozzle was better than the straight nozzle and the bore hole and it would be improved with the increasing of nozzle diameter and the differential pressure. The rape seeds were selected as experimental material, the optimum parameters combined with conical nozzle of Ф1 mm, the roller＇s rotational speed of 14 r/min, and the differential pressure of 2 kPa were received through orthogonal tests. The parameters were tested to be the best with the seeds single pickup ratio of 92 %, the seeds missing pickup ratio of 4 % and the seeds multiple pickup ratio of 4 %.

关 键 词：精密排种器 气吸式 吸种性能 CFD 数值模拟 试验 

分 类 号：S223.2[农业科学—农业机械化工程]