四旋翼轴距对喷雾雾滴沉积特性的影响

The Effect of Four-rotor Wheelbase on Spray Droplet Deposition Characteristics

为研究旋翼轴距变化对喷施雾滴沉积的影响,以四旋翼无人机为对象,建立了四旋翼喷雾沉降仿真模型,并进行风速试验验证计算模型正确性。通过改变四旋翼的轴距,分别研究了不同旋翼距径比下旋翼气流的聚合流动变化;通过引入离散相喷雾模型,对不同距径比的四旋翼风场中的雾滴沉积及其粒径分布进行分析,以探究四旋翼轴距对雾滴沉积特性的影响。模拟结果表明:旋翼气流对雾滴产生下压作用,从而促进了雾滴的沉降,提高了雾滴的抗漂移能力;当旋翼轴距变小时,旋翼间下洗气流会发生聚合流动,轴距越小,气流聚合程度越高,带动雾滴沉积且增大了雾滴对前飞来流的抵抗能力;下洗气流聚合现象对小粒径雾滴的沉积有促进作用。

In order to study the effect of four-rotor wheelbase on spray droplet deposition characteristics.The four-rotor UAV spray settlement simulation model was established and the wind speed test was carried out to verify the correctness of the calculation model.By changing the wheelbase of the four rotors,the downwash flow aggregation phenomenon were studied when the wheelbase-to-diameter ratios change.By introducing the discrete phase spray model,the deposition and particle size distribution in the four-rotor wind field were analyzed to investigate the effect of the four-rotor wheelbase on the droplet deposition characteristics.The simulation results show that the rotor airflow exerts a downward pressure on the droplets,which promotes the deposition of the droplets and improves the anti-drift ability of the droplets.When the rotor wheelbase becomes smaller,the downwash airflow between the rotors will aggregate.The smaller the wheelbase is,the higher the degree of airflow aggregation,which will promote the deposition of droplets and increase the resistance of the droplets to the forward flow.The rotor downwash airflow aggregation phenomenon promotes the deposition of small particle size droplets.