气吸滚筒式棉花精密排种器流场数值模拟与试验

Numerical Simulation and Experiment of Pneumatic Cylinder Precision Seed-metering Device

针对气吸式精密排种器充种、携种阶段存在充种精度不高的问题,从提高排种器充种性能和精度出发,以气吸滚筒式精密排种器为研究对象,建立流场模型,利用Fluent软件对影响充种性能的滚筒负压腔负压与吸孔直径进行数值模拟,探究不同影响因素对排种器内部压力场与速度场变化规律的影响。通过试验对仿真进行验证,并以滚筒转速、吸孔直径、负压为影响因素,对排种器合格指数、漏播指数和重播指数进行试验研究,结果表明:在滚筒转速15.38r/min、吸孔直径3.59mm、负压5.04kPa时,排种器的排种合格指数为93.3%,漏播指数为2.58%,重播指数为4.25%,排种效果最好。

For the air-suction precision seed metering device,there is a problem of low filling accuracy in the filling and carrying stages.Starting from improving the filling performance and precision of the seed metering device.The gas suction drum type precision seed metering device is the research object.The flow field model of the suction drum type precision metering device was established.The numerical simulation of the negative pressure and suction hole diameter of the negative pressure chamber affecting the filling performance was carried out by Fluent software.The internal pressure field and velocity of the seeding device were investigated by different influencing factors.The influence of the law of field variation.The simulation was verified by experiments.The test was carried out by using the rotation speed of the drum,the diameter of the suction hole and the negative pressure as the influencing factors.The qualified index,,the leakage index and the replay index of the seed meter were tested to obtain the best filling parameters:the drum rotation speed was 15.38 r/min and the suction hole diameter was 3.59 mm.and the negative pressure are 5.04 kPa.At this time,the seeding performance of the seed meter is the best,the qualified index is 93.17%,the leakage index is 2.58%,,and the replay index is 4.25%,which meets the agronomic requirements of cotton planting.