Numerical Analysis of Spreading Process of Ellipsoidal Spraying Droplet Impacting on Superhydrophobic Surface

  • Qingmin Pan School of Mechanical Engineering, Anhui University of Technology, China
  • Deyu Tu School of Mechanical Engineering, Anhui University of Technology, China
  • Baohong Tong School of Mechanical Engineering, Anhui University of Technology, China
  • Yongguang Hu School of Agricultural Engineering, Jiangsu University, China
  • Tao Wang School of Mechanical Engineering, Anhui University of Technology, China
Keywords: ellipsoidal droplet, kinetic behavior, pesticide spray, gas-liquid flow, spreading factor, interface tracking environmental impact


Agricultural spray deposition is especially important for pesticide application because low efficiency can lead to environmental pollution, poor biological efficiency and economic loss. The deposition of pesticide spray on the leave surfaces is related to the impact kinetic behavior of droplets. But after considering the deformation of the droplet, how impingement will affect the deposition is an interesting research. In this study, a superhydrophobic surface was used to replace the plant surface that the pesticide droplets may affect. An interface tracking method was proposed to characterize the impingement dynamics behaviors of different ellipsoid droplets impacting on the surface. The maximum spreading coefficient and time of ellipsoidal droplets increased with the raise of their size. A lower sized droplet has a faster spreading rate, while the center of a higher sized droplet is thinner. As the velocity of pesticide increases, maximum spreading coefficient of droplet increases with a decrease in the maximum spreading time of droplet. The simulation results can contribute to provide theoretical basis for improving spray efficiency.


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