雾化网格在果树植保喷雾中的应用与试验  

Application and experiments of the atomization mesh used on the plant protection spraying in orchards

作　　者：薛秀云 杨振宇 梁馨琪 罗钦 吕石磊 李震 Xue Xiuyun;Yang Zhenyu;Liang Xinqi;Luo Qin;Lyu Shilei;Li Zhen(College of Electronic Engineering,South China Agricultural University,Guangzhou 510642,China;Division of Citrus Machinery,China Agriculture Research System,Guangzhou 510642,China;Key Laboratory of Smart Agricultural Technology in Tropical South China,Ministry of Agriculture and Rural Affairs,Guangzhou 510642,China;Meizhou SCAU-Zhensheng Research Institute for Modern Agricultural Equipment,Meizhou 514781,China)

机构地区：[1]华南农业大学电子工程学院,广州510642 [2]国家柑橘产业技术体系机械研究室,广州510642 [3]农业农村部华南热带智慧农业技术重点实验室,广州510642 [4]梅州市华农大振声现代农业装备研究院,梅州514781

出　　处：《农业工程学报》2022年第18期1-10,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(31971797,32271997);财政部和农业农村部:国家现代农业产业技术体系资助项目;国家重点研发计划项目(2020YFD1000107);广东省现代农业产业技术体系创新团队建设专项资金(2022KJ108)。

摘　　要：针对目前一些植保机械在喷洒农药的过程中难以兼顾低飘移和高沉积的问题,该研究将雾化网格应用在果树植保喷雾作业中,使喷头喷出的大粒径雾滴在接近靶标处撞击网格二次雾化为小雾滴。为了研究雾滴撞击网格后的粒径和速度分布以及沉积特性,以网格孔径、喷头与网格的距离为变量,以二次雾化后雾滴的速度和粒径分布、喷雾角、雾滴覆盖率、沉积量和飘移量为指标进行试验研究。试验结果表明:放置孔径为461、350和227μm网格时测量点的雾滴平均速度比没有网格时的2.35 m/s分别降低23.40%、13.90%、29.00%,最大平均粒径比没有网格情况下的192.5μm分别降低19.5%、14%、10%;随着网格孔径的减小,二次雾化后雾滴的喷雾角有逐渐降低的趋势;放置350和227μm孔径网格时果树冠层各层内沉积均匀性相近,沉积量变异系数最高分别为88.08%和74.22%,远低于461μm孔径网格的162.98%;放置350μm孔径网格时雾滴穿透性较好,各层之间沉积量变异系数最高为10.08%,低于461和227μm孔径网格的44.09%和18.25%。在该研究试验条件下,350μm孔径网格的沉积效果优于461和227μm孔径网格,喷头与网格的距离对雾滴覆盖率和沉积量没有显著影响,使用雾化网格的雾滴飘移较少,非靶标区平均雾滴飘移量为靶标区沉积量的7.58%。研究结果可为果园无人机喷雾作业优化提供参考。Plant protection spraying has been the main way to prevent crops from pests and diseases at present.However,the average utilization rate of pesticides is only 20%to 30%in manual sprayers and large-capacity rain spraying,particularly with water consumption of 600-1200 L/hm2.The current pesticide spraying cannot fully meet the requirement of intensive agriculture in recent years.Among them,a large number of droplets with small particle sizes are susceptible to drifting by ambient wind.In this study,the mesh atomization of droplets was applied to reduce the wind drift for the high utilization rate of pesticides in the process of plant protection spraying.A systematic optimization was also made to investigate the secondary atomization characteristics of the droplets and the deposition effect of the droplets after the spray hits the mesh.The experimental variables were set as the pore size and the distance between the nozzle and the mesh.Phase Doppler Anemometry(PDA)was used to measure the velocity and particle size distribution of droplets after secondary atomization.A high-speed camera was selected to capture the spray angle.A 0.5 g/L methyl orange aqueous solution was prepared as a spray solution.The water-sensitive and filter tests were carried out to determine the droplet coverage and deposition amount,in order to evaluate the droplet deposition characteristics of the mesh atomization.The test results showed that:1)the mesh effectively reduced the speed of the droplets.The average velocities of the measurement points were 1.80,2.02,and 1.67 m/s under the mesh with pore sizes of 461,350,and 227μm,respectively.There were 23.40%,13.90%,and 29.00%lower than those without the mesh(2.35 m/s).2)The mesh reduced the particle size of the droplets.The maximum average particle sizes of the measurement points were 155.0,165.6,and 173.3μm under the mesh with the pore size of 461,350,and 227μm,respectively,which were 19.5%,14%,and 10%lower than those without the mesh(192.5μm).3)The spray angle of the droplet was varied in

关 键 词：喷雾 UAV 雾滴破碎 金属丝网 覆盖率 沉积量 

分 类 号：S491[农业科学—植物保护]