Establishment of fog droplet distribution model and study on canopy deposition uniformity

Abstract

In plant protection operations, the distribution of droplets affects the atomization effect. To make the distribution of fog droplets more uniform in the air field, a fog droplet distribution model was established based on a three-dimensional motion model of droplets and the particle size distribution function, combined with a two-dimensional normal distribution function. The effects of the initial incidence angle and the additional wind speed on the distribution of fog droplets were analyzed. The fog droplet distribution was simulated to analyze the droplet distribution in the spatial layer, which was compared with the experimental results. To investigate the impacts of different factors on the atomization distribution, the Lagrangian interpolation method was employed, and the optimal initial incidence angle and external wind speed were found. When the initial angle of incidence was 17°, the slope of the fitted curve was the smallest, with a coefficient of determination of 0.9622 and a relative error of 3.12%. With an additional wind speed of 0.1 m/s, the coefficient of determination was 0.9782, with an average error of 4.61%. The simulation results were consistent with the experimental findings, and the accuracy of the fog droplet distribution model was verified. In summary, this research provides a novel method to improve the uniformity of the droplet distribution, which can provide a theoretical basis for determining the operating parameters.