风送式喷雾机风筒结构设计与试验研究

Structural Modification and Experiment on Air Duct of Air-assisted Sprayer

基于棉花喷施落叶剂的需求,针对现有的棉花风送式施药机,设计了一种风送式喷雾机风筒,并利用计算流体动力学(CFD)仿真技术对风送式喷雾机风筒内外流场的三维区域进行了仿真,研究风筒气流场分布。仿真结果表明:风筒4个出风口处的速度分布均匀,整个风筒内流场区域风速变异系数较小。同时,通过试验验证了该仿真模型的可靠性,并将设计的风筒安装在喷雾机上进行实际大田作业,检验风送式喷雾机的雾滴沉积分布情况。试验结果表明:棉花整个冠层的叶片正面雾滴沉积率达到了79.58%,叶片反面雾滴沉积率达到了33.38%,冠层上部、中部、下部叶片正反面雾滴平均沉积率相差均<1 0%,整个冠层雾滴沉积分布均匀性较好。

In order to improve the mechanized spraying effect of cotton,based on the existing spray boom sprayer,the air duct of air-assisted sprayer was designed. 3-D flow field of interior duct and exterior free flow region was simulated by usingcomputational fluid dynamics（ CFD）. Flow field analysis of the simulation results showed that the velocity distribution uniformity of four outlets,the coefficient variation was smaller in whole flow region,through the experiment to verify the reliability of the simulation model,then the air duct was equipped with the air-assisted sprayer to do an experiment in the actual field,through the experiment,it can check the situation of spray deposit distribution,spray deposit distribution test showed the front leaves average of inside cotton canopy was 79. 58% and the back leaves average droplet coverageof inside cotton canopy was 33. 38%. The biggest difference of front leaves average droplet coverage among upper canopy,middle canopy and lower canopy less than 10%,the spray deposit distribution uniformity of the whole cotton canopy was better.