为了提高植保作业中喷雾器的喷雾效果,将高压静电喷雾技术与气力式喷雾技术结合,设计了气力式静电喷枪。该喷雾器由充电式镍氢电池、高压静电发生器、喷枪主体、静电喷头组成,采用感应充电的方式对雾滴进行充电。对喷枪的喷幅进行了测量,用法拉第筒法测量了荷质比,用PIV(particle image velocimetry)NI]速系统测量了雾滴运动速度分布,最后用浓度测试法测量了雾滴沉积率。结果表明:静电作用可使喷枪喷幅变宽;荷质比随气体压力的加大而增长;静电作用能提高雾滴运动速度且使雾滴运动速度分布更加均匀;静电作用能提高雾滴在叶片上的沉积率,尤其能提高叶片背面的沉积率,从而使雾滴能够均匀吸附于作物表面各部位。
To improve the effectiveness of sprayer in the process of plant protection spraying, we designed an air-assisted spray gun that combines the high-voltage electrostatic spray and the air assisted spray. The spray gun is composed of a rechargeable nickel-metal hydride battery, a high-voltage electrostatic generator, the main body, and an electrostatic nozzle. The spray droplets were charge by using the induction method. We measured the gun's spraying swath, utilized the Faraday cup method to test the charge-to-mass ratio of the gun, adopted PIV (particle image velocimetry) system to measure the spray droplets' velocity distribution, and used the concentration collecting method to test the deposition of the droplets. It is concluded that the electrostatic effect helps to widen the spraying swath. The charge-to-mass ratio increases with gas pressure. The electrostatic effect raises the droplets' velocities while making the velocity distribution evener. The electrostatic effect improves the droplets deposition on leaf blades, especially on their backs, so the droplets will attach to leaf blades more evenly.