Fluid flow analysis of low-altitute agricultural UAV pesticide spraying device / Han Dan

• Main Author: Han, Dan
• Format: Thesis
• Published: 2020
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://studentsrepo.um.edu.my/12117/1/Han_Dan.jpg; http://studentsrepo.um.edu.my/12117/8/han_dan.pdf; http://studentsrepo.um.edu.my/12117/

The nozzle is an important part of the drone pesticide spraying device. The quality of the nozzle directly affects the atomization performance. Fan nozzles are widely used in the field of plant protection in agriculture, forestry, pest control, and weed removal. When using drones to spray pesticides, the spraying velocity, the spraying range of the pesticides, and the atomized particle size are all key factors that directly affect the efficiency of pesticide use. This paper uses SOLIDWORKS and ANSYS software to design and simulate. The boundary conditions are kept the same, and the influence of the nozzle's grooving angle (α), nozzle cavity diameter (D), and nozzle throat length (L) on fluid velocity, pressure, and mass flow is measured. Then, this project report compares and studies the influence of the changes of different structural parameters on the internal flow field of the combined flat fan nozzle, and find the influence relationship between different structural parameters and nozzle atomization performance; and the best structure corresponding to the nozzle with the optimal atomization performance parameter combination. Pesticide residues and droplet drift are minimized to reduce pesticide waste and environmental pollution. The research observes the pressure and velocity distribution of the fluid flow inside the nozzle. By comparing the results concluded that the fluid flows from the nozzle inlet to the nozzle outlet, the pressure of the flow field inside the nozzle gradually decreases, and the velocity gradually increases. The pressure and velocity at the nozzle groove vary the most. The grooving angle of the nozzle has the greatest influence on the fluid velocity and spraying range. The cavity diameter and grooving angle of the fan nozzle have the greatest influence on the mass flow. The nozzle cavity diameter and throat length have a small effect on fluid velocity. The shape and droplet quality of the spray of the combined iv flat fan nozzle is better than the flat fan nozzle. The simulation results of 13 combined flat fan nozzles are compared and analyzed comprehensively, and the nozzle structure parameters are combined as follows: the nozzle with the parameters of α=35°, d=3mm, l=2mm has the best atomization performance out of the 13 nozzles.