基于CFD果园风送式喷雾机雾滴沉积特性研究
Droplet deposition characteristics of CFD based orchard air driven sprayer

自制应用于柑橘园施药的风送式喷雾机,并基于CFD建立喷雾机雾滴运动轨迹及沉积模型,考察该喷雾机雾滴沉积特性及送风方向对雾滴沉积的影响。根据喷雾机尺寸参数，建立喷雾流场二维模型，并确定DPM模型参数，模拟获得距喷头不同距离的垂直截面上雾滴沉积量。试验结果显示:在距喷头1.0 m的范围内，雾滴沉积特性与试验结果相符，且在1.0 m范围内，送风角度的增加对雾滴飘移影响较小，随着与喷头距离的增大，送风角度对底部雾滴飘移损失的影响逐渐加剧；在距喷头1.0 m范围以外，雾滴沉积特性与实际试验结果偏差较大，但雾滴沉积量随与喷头距离的增大而逐渐减少的规律是一致的。
The CFD based droplet trajectory and deposition model were established to study the droplet deposition characteristics and the influence of air supply direction on droplet movement in the sprayer. The relevant parameters of the sprayer were measured. Two dimensional spray flow model was established and the parameters of the model were determined. The droplet deposition on vertical section at different distances from sprinkler head was simulated. Validation test was conducted under the same conditions as the simulation. The results showed that the droplet deposition characteristics fitted well with the results tested. The increase of air supply angle had little effect on droplet drift within the range of 1.0 m from the sprinkler head. With the increase of the distance from the sprinkler head,the influence of air supply angle on the drift loss of fog droplets at the bottom increased gradually. The simulation results deviated greatly from the actual test results when the range of the sprinkler head exceeded the 1.0 m,but the rule of decreasing droplet deposition gradually with the increase of distance from sprinkler head was consistent.