离心式油菜精量排种器型孔结构设计与试验

Design and Experiment on Metering Hole Structure of Centrifugal Precision Metering Device for Rapeseed

针对传统机械离心式油菜排种器型孔易出现堵塞导致后续断条的问题,进行了离心式油菜精量排种器型孔结构的研究,分析了型孔囊取1、2、3粒油菜种子的临界直径;结合EDEM种子运动轨迹的仿真分析得到了型孔囊取1、2、3粒种子的临界值分别为2.6、3.5、3.8 mm;同时试验研究了型孔直径、转速与排种性能关系,进行了型孔堵塞统计试验。结果表明:改进后型孔直径取3.8 mm时,其总排量稳定性变异系数不大于14.8%,各行排量一致性变异系数不大于16.4%,型孔无堵塞现象。

Based on problem that metering holes of centrifugal metering device were easily blocked and led to broken rows,the influential factors on blocking of metering hole was analyzed to develop a new structure of metering hole. The critical diameter of metering hole which only took one seed,two seeds or three seeds were determined via the model of relationship among rotation speed,structural parameters of hole and geometric properties of rapeseed. Combined with simulation of trajectory of seeds via discrete element method( DEM) software EDEM,the relevant critical diameter values of metering hole which only took one seed,two seeds or three seeds were 2. 6 mm,3. 5 mm and 3. 8 mm,respectively. The test research was carried out to achieve the relationship of hole diameter,rotate speed and the performance of metering device. Experiment results showed that when the hole diameter was 3. 8 mm, variation coefficient of spacing row consistency and stability of full seeding quantity were less than 16. 4% and14. 8%,respectively,and there was no blocked hole.