玉米大豆兼用腔盘组合孔式排种盘设计与充种性能试验

Design and Seed Filling Performance Test of Cavity Plate Combination Hole Type Seeding Plate for Corn and Soybean

针对玉米大豆带状复合种植条件下传统机械式排种器不易实现二者兼用精量排种要求、现有气力式排种器排种速度提高因型孔漏充存在漏播断条等问题,设计了一种具有腔盘组合孔结构的排种盘,分析确定了排种盘关键结构参数,构建了吸附过程和吸运过程力学模型。应用EDEM离散元仿真与台架试验相结合的方法进行了排种盘型式优选试验,结果得出:腔盘组合孔式排种盘具有提高充种室种群定向运移平均速度和增大拖拽充种角的作用,有效抑制了型孔漏充率。以安装优选种盘的玉豆兼用排种器为对象,以机组前进速度和工作负压为试验因素,以漏充率和充种合格率为试验指标,采用二因素全因子试验设计开展了充种性能试验,结果表明:当机组前进速度为4.0~7.0 km/h、工作负压在3.0~4.0 kPa时,玉米和大豆种子漏充率均小于3.6%、充种合格率均不小于96%。田间验证试验表明,在机组前进速度为4.0~7.0 km/h、工作负压为3.0~4.0 kPa条件下,腔盘组合孔式排种盘的排种器播种玉米和大豆漏充率分别不大于3.8%、4.2%;当工作负压为3.0 kPa、机组前进速度为7.0 km/h时,自扰动腔盘组合孔式排种盘相比无扰动平面排种盘,播种玉米和大豆漏充率分别下降14.8、12.6个百分点。

For corn and soybean belt compound planting conditions under the traditional mechanical seed metering device is not easy to realize both precision seed discharge requirements,the existing pneumatic seed metering device seed discharge speed due to leakage of holes leakage charging exists leakage sowing broken stripes and other issues,a cavity plate combined hole structure of the seeding plate was designed and analyzed to determine the key structural parameters of the seeding plate,and the adsorption process and suction and transportation process mechanics model was constructed.EDEM discrete element simulation and bench test were combined to carry out the seeding plate type selection test,and the results concluded that the cavity plate combined hole seeding plate had the effect of improving the average speed of directional transport of seed populations in the seed filling chamber and increasing the dragging angle of seed filling,which effectively suppressed the leakage rate of the hole.With the installation of the preferred seed plate of the jade and soybean hybrid seed metering device as the object,with the unit forward speed and negative pressure as the test factors,with the leakage rate and the seed filling rate as the test indexes,the two-factor full factorial experimental design was done to carry out the seed filling performance test,and the results showed that when the unit forward speed was 4.0~7.0 km/h,the work of the negative pressure was 3.0~4.0 kPa,the leakage rate of maize and soybean seeds was less than 3.6%,and the qualified rate of seed filling was not less than 96%.Field verification test showed that under the conditions of unit forward speed of 4.0~7.0 km/h and working negative pressure of 3.0~4.0 kPa,the leakage rate of corn and soybean seeds sown by the seed metering device of cavity plate combination hole-type seed metering device was no more than 3.8%and 4.2%,respectively.When the working negative pressure was 3.0 kPa and the forward speed of the unit was 7.0 km/h,the leakage rate of sowing corn and soybeans was decreased by 14.8 and 12.6 percentage points,respectively,compared with that of the undisturbed flat seeding plate with the combination of holes in the self-disturbing cavity plate.