Design of an Expandable Air-assisted Spray Implement

Abstract. In order to meet the requirements of ventilation and lighting, the standardized orchards are generally wide-row spaced, with a 4~5 meters row spacing. The planting position of fruit trees is about 1.5 meters higher than the ground to ensure the drainage demand. It is difficult for not only miniaturized plant-protection equipment to meet the requirements of simultaneous spraying to both sides, but also for large devices to turn over in, into or out of orchards. In order to deal with this limitation, this paper proposes and designs an expandable air-assisted spray implement. The expandable unit was designed to achieve simultaneous operation on both sides and the air-assisted spray technology was applied to spray fruit trees on both sides to ensure droplet penetration. The airflow distributor is designed, the airflow generated by the fan is evenly distributed to the nozzle to ensure the airflow uniformity. CFD simulation and Laboratory tests are carried out on the air distributor, the reasons for the difference between the simulation results and the test results are analyzed, and the improvement plan is proposed. The design of this implement provides a reference for the development of plant-protection machinery for orchards.