Design And Experiment Of An Electrostatic Sprayer With On-Line Mixing System For Orchard

Plant protection is an important part of modern agricultural production. The current plant protection methods include chemical, physical, biological and integrated control and so on. Chemical control is an efficient, fast, timely prevention and other characteristics, especially for sudden, large-scale outbreak of pests, can be done quickly and effectively control. Therefore, chemical control will continue to be the main method of plant protection operations for crop pest control. Due to the limitation of terrain conditions, the development of orchard spraying machine in the South Hilly area lags behind compared with field crops spraying machinery development. It's difficult to popularize medium and large spraying machinery. Lightweight sprayer will remain the mainstream. Currently, potions mixing of sprayer generally use premixed formula. This approach is prone to nonuniformity mixing drugs, waste problem of excess premixed potions and potions corrosion phenomenon of pump. Meanwhile, with the increasing amount of pesticide and growing concern about the environment and food safety issues, effect of spray drift has become one of the major problems that need attention. Therefore, timely adjustment of product structure is necessary. According to the characteristics of different agricultural areas, work out the sprayer of modern agricultural plant protection machinery that is suitable for the different parts in order to promote the utilization of pesticide.In this paper, according to the orchard planting pattern in the South Hilly area, an electrostatic sprayer with on-line mixing system for orchard is designed. By conducting the experiment of effects of nozzle type and spray angle on spray deposition, the experiment of mixed drugs performance of on-line mixing system and the experiment of droplet drift of electrostatic spraying system, the rule of the influence of main parameters on spray performance is got. The results show that:1) HH-SS1 standard solid cone nozzle-15°?HU-SS60-02 standard flat fan nozzle-30° and HU-SS60-03 standard flat fan nozzle-30° nozzle configurations perform best at the upper side of leaves. The highest effect on depositions on at the bottom side of leaves are found for HH-SS1 + 30° ? HU-SS60-02 + 30° and HU-SS60-03 + 45° nozzle configurations. On the vertical plane, the change of spray angle will affect the distribution of droplet deposition.2) The mixing uniformity and stability were evaluated experimentally under the conditions that the mixture proportion of 0.1%, 0.2% and 0.3% and the sprayer pressure of 0.50, 0.75 and 1.00 MPa. The measured maximum variable coefficients of mixing uniformity and stability were 4.46% and 3.51% respectively. The results indicate that the proposed online mixing system has good mixing performance.3) At the same lateral wind speed, increasing electrostatic voltage could improve the spray drift. When the lateral wind speed is 4 m/s, the droplet drift distance of 4~8 k V electrostatic spraying was more than 0.9 m, the droplet drift percentage was more than 30%. It suggested that when spraying is conducted under the high wind speed, the low voltage spraying or non-electrostatic spraying should be used.4) With air-assisted electrostatic spraying system, the droplet adhesion rates in the upper side of the deposition shelf, which increased by 9.3%, 46.3% and 53.2% respectively compared to those of non-air-assisted electrostatic spraying system. The droplet adhesion rates in the bottom side of the deposition shelf which increased by 82.9%, 164.3% and 184.2% respectively compared to those of non-air-assisted electrostatic spraying system. the droplet adhesion rates in the upper and bottom side of the interior of artificial tree canopy were 48 and 37 /cm respectively with air-assisted electrostatic spraying system, which increased by 166.7% and 428.6% respectively compared to those of non-air-assisted electrostatic spraying system. The results indicate that the air-assisted electrostatic spraying system can improve the performance of spray deposition and spray penetration, while using air-assisted spraying system can effectively suppress droplet drift phenomenon.