锥盘排种器离心推送结构设计与充种机理分析

Design on Push Structure of Centrifugal Cone Seed-metering Device and Its Filling Mechanism Analysis

针对机械式排种器高速作业时存在的排种稳定性问题,提出了一种离心锥盘推送式充种方式,分析了影响籽粒在种腔内部充填性能的应力种类与力学规律,建立复合充填应力数学模型,通过理论分析找出提高充填力的有效方式,并借助Matlab与ORIRIN逐步修整数学模型,从而确定关键结构最优参数值。采用离散元仿真软件EDEM虚拟仿真并通过单体台架试验,对有离心推送结构和普通空腔结构的离心锥盘排种器进行对比试验,验证了附加离心推送结构的优越性。试验结果表明,在7~13 km/h高速作业区,其平均漏播指数降低了2.52%,同时,利用后处理功能所测得的标记颗粒充填力数值变化规律与预测值变化趋势基本一致,验证了理论模型的可行性,最大限度发挥了种层离心力对预充填籽粒的作用,且进一步扩大了有效充种区域。

Aiming at the bottleneck problem that hinders the high-speed work development of mechanical seed-metering device,a kind of centrifugal cone direction push way for grain filling was proposed,the influence of the grain in the internal cavity filling properties of stress types and mechanical laws was analyzed,the composite filling stress mathematical model was established,the effective way to improve the filling force was found out through theoretical analysis,and the mathematical model was gradually dressed with the help of Matlab and ORIRIN drawing software to determine the optimal key structure parameters. Through the single bench test using discrete element simulation software EDEM virtual simulation of centrifugal push structure,and the cavity structure of centrifugal cone disc metering device were tested,the superiority of additional centrifugal push structure was demonstrated,test results showed that in the 7 ~ 13 km/h high speed operation,the average leakage sowing index of Indus cavity structure cone disc metering device was reduced by 2. 52%,at the same time,the postprocessing function measured marker granule filling variation and numerical prediction value basically had the same trend,which verified the feasibility of the theoretical model,maximized the play of a layer of centrifugal force on the pre filling grain,and to further expand the effective filling area,the study provided theoretical basis and reference for the centrifugal cone type high-speed exhaust device design and development.