Droplet Deposition Characteristics of Conical Wind Field Anti-drift Device

Drifting and settling of droplets are important factors affecting the effect of spray machinery. In order to reduce the drift of droplets and the ineffective settlement in non-target areas, a conical wind field anti-drift device was designed. The effect of conical wind field on droplet deposition was clarified by three factors and three horizontal indoor droplet drift deposition tests. The experimental results showed that these three factors had significant influence on the deposition characteristics of droplets, and the degree of influence was as follows: conical wind speed, natural wind speed, and spray pressure. As an example of natural wind speed of 2 m/s, the mean diameter of droplet volume was decreased by 11.7%, and the coverage, deposition density and deposition volume was increased by 21.9%, 26.7% and 22.6%, respectively. The optimization results of response surface model showed that when the spray pressure was 0.34 MPa, the conical wind speed was 16.53 m/s, the optimal droplet deposition can be 3.14 μL/cm2 when the natural wind speed was 2 m/s. If the natural wind speed was more than 2 m/s, the spray pressure should be reduced and the conical wind speed should be increased, so as to ensure the better droplet deposition. The test verification results were basically consistent with the model prediction. The research result can provide a reference for further promoting the application of airflow assisted technology in plant protection field. © 2020, Chinese Society of Agricultural Machinery. All right reserved.