Development And Experiment Of Mechanical Efficiency Measurement System For Aerial Spraying Air-driven Atomizer

Aviation application in agriculture has the characteristics of high working efficiency,good terrain adaptability and strong controllability,which makes up for the shortcomings of traditional pesticide application instruments and manual pesticide application.It has developed rapidly in the field of plant protection recently.When the plant protection machine carries out aerial spraying,it is far away from the targeted application area,and the particle size of spray droplets is an important factor affecting droplet drift and droplet deposition.However,when the liquid medicine is broken to a certain extent,it will eventually fall on the target,and its energy consumption is exerted by the atomizer.The energy consumed by droplet breaking is necessarily related to atomizer and aircraft.The energy consumed by the droplet crushing to a certain volume is fixed,but if the atomizer applying crushing energy produces too much energy,it will inevitably cause energy loss and waste,affect the endurance and use efficiency of the aircraft,cause unnecessary energy waste and pollution,and finally affect the application effect.In order to explore the mechanical efficiency of atomizer when the liquid medicine is broken to the size of applicable droplets,this paper studies and designs the mechanical efficiency measurement system of air-driven atomizer for plant protection manned machine.The experiments and assignments studied in this paper are as follows:(1)The theoretical analysis of the crushing energy of droplets and the research on the crushing mechanism of droplets,as well as the specific research and analysis of the atomization methods in the spraying process of agricultural aviation pesticide application,have determined the overall design scheme and system composition of the mechanical efficiency measurement system of agricultural aviation pesticide application air-driven atomizer according to the characteristics of aviation pesticide application such as fast flight speed and large flow rate,and combined with the requirements of mechanical efficiency measurement.(2)Completed the design of mechanical efficiency measurement system of air-driven atomizer for aviation pesticide application,including the purchase and selection of experimental equipment,the selection of electronic components and the drawing and design of circuits in SOB,the compilation of software program codes in SOB board and the setting of parameters in software programs.AU5000 rotary atomizer was selected as the wind-driven atomizer in this experiment,and it was introduced to ensure that the pesticide application in this experiment could be carried out completely.The hardware circuit design of mechanical efficiency measurement system of airdriven atomizer for agricultural aviation pesticide application was completed.The independent design of SOB was completed by AD20 software,and the built-in peripherals were integrated on a board.Solidworks was used to design the shell for the onboard system to prevent the liquid medicine from corroding the control board and causing short circuit.The data transmission and reception of sensors was completed based on RS-485 protocol,and the system control program was written by Keil5.(3)Completed the empirical formula model of mechanical efficiency measurement system of air-driven atomizer for agricultural aviation pesticide application.In the aerial pesticide application laboratory in Xiaotangshan Agricultural Demonstration Base of Beijing Academy of Agricultural and Forestry Sciences,IEA-1 high-speed wind tunnel was used to set up an experimental platform for measuring the mechanical efficiency of aerial pesticide application airdriven atomizer,and AU5000 air-driven rotating cage centrifugal atomizer was used to conduct several groups of repeated experiments of variable control for pesticide application equipment,and the correlation among operating wind speed,pesticide application flow rate,atomizer equipment parameters(blade angle),traction force and droplet spectrum parameters was analyzed.(4)Completed the construction of mechanical efficiency measurement system of air-driven atomizer for aviation pesticide application,designed the experimental method and process,and expounded and analyzed the experimental results.The experimental analysis is divided into atomization characteristic analysis and mechanical efficiency analysis.