负压驱动水稻精量直播排种器设计与试验研究

为满足目前农户和育种专家对水稻精量穴直播的农艺种植要求,减少育秧插秧环节的人工劳动强度,采用储种仓预充种、负压多孔吸种、高压气力排种与清堵等多种方式和技术,设计开发了一种气力圆盘式水稻穴精量直播排种器,并采用有限元分析软件Fluent15. 0分析了吸种孔的孔径、吸种盘厚度的对气室内部压强、气流速度的作用,进而研究对排种性能的影响。将开发的排种器在自行改造的试验台架上进行了正交试验,研究了吸种孔的尺寸、圆盘转速、负压真空度对排种器排种性能的影响。结果表明:影响排种器排种性能的主次因素依次为:吸种孔直径尺寸、吸种盘的转速和气室的真空度,确定了排种器较为合理的参数:对于圆柱型吸种孔,孔的直径为1.4 mm、转速为30～35 r/min、气室负压值为1. 2～1. 4 k Pa时达到育种要求。同时,对优化后的排种器(吸种盘转速35 r/min、吸种孔直径1. 4 mm和气室负压值1. 4 k Pa)进行台架试验,结果表明:播种合格率为84. 22%,重播率为8.81%,漏播率为5. 97%,满足JB/T 10293-2013《单粒(精密)播种机技术条件》中的参数指标。

Design and Experimental Study of Negative Pressure Precision Seed-metering Device for Rice

In order to meet the current agronomical planting requirements of farmers and breeding experts on rice seedlings,reducing the labor intensity of breeding seedlings and transplanting,This paper uses storage silos to fill rice seeds in advance,negative pressure adsorption rice seeds,high pressure airflow to clear seeds and various methods and techniques.Designed and developed a precision seed-metering device,The finite element analysis software Fluent 15.0 was used to analyze the effect of the hole diameter of the seed suction hole,the thickness of the suction seed plate on the pressure inside the air chamber,and the air flow velocity,and then studied the effect on the seed discharging performance.The developed seedling device was subjected to orthogonal test on a self-renovated test bench.The effects of suction hole size,disc rotation speed and vacuum degree on seed removal performance of seedling device were studied.The results show,the factors affecting seed metering performance are in turn:Suction hole diameter size,Disk speed,Vacuum degree,Determined the more reasonable parameters of the metering device:Cylindrical suction hole,the diameter of the hole is 1.4mm,Speed is 30-35r/min,Negative pressure value is 1.2-1.4kPa,at the same time,test the optimized seed-metering device(Speed is 35r/min,The diameter of the hole is 1.4mm,Negative pressure value is 1.4kPa).Test result display:the pass rate of sowing is 84.22%,replay rate is 8.81%,leakage rate is 5.97%.These testing results fully coincide with the standard JB/T 10293-2013 specification of single seed drill(precision drill).