风送式水稻撒播机关键部件设计及试验

Design and Test of Key Parts on Air-assisted Rice Broadcast Sower

设计一种新型风送式水稻撒播机以满足机械撒播需要。采用Fluent中的Mixture多相流模型,对风送管内气、固两相流进行数值模拟,对比平嘴、圆弧嘴、扁喇叭嘴3种喷嘴结构对出口气流速度及种子浓度分布的影响,并制作样机,进行试验验证。试验表明:数值仿真模拟符合试验规律,平嘴风送管能满足水稻撒播均匀性的要求;公顷播量为120kg时,在(0.2×0.2)m^2的区域内播种17粒左右,标准偏差为1.49,波动量较小,能满足撒播均匀性的要求。

This paper designed an air-assisted rice broadcast sower to satisfy the requirement of mechanized seeding. The numerical simulation was performed using the Mixture model of Fluent software. The influence of flat, circular arc and flat horn nozzle on flow rate and seed concentrate at the outlet of air pipe was also analyzed. The prototype testing device was made to verify the results of numerical simulation. The test show that the results of numerical simulation conform to experi- mental rule and the flat nozzle can satisfy the uniformity requirement of broadcast. When the seed quantity is 8kg/mu, the number of seed at the area of 0.2×0.2m^2 is about 17 and the standard deviation is 1.49. The air-assisted rice broadcast sower can meet the requirement of sowing uniformity.