Optimization of Diversion Device and Experiment on Air-assisted Sprayers in Orchards

Abstract

In order to improve the velocity distribution of the airflow field generated by the air-assisted sprayer in the orchard, a flow field distribution model of the sprayer air delivery system based on CFD simulation is designed. The airflow field distribution of the air-assisted operation is obtained through FLUENT simulation. The calculation domain includes the internal flow field and external flow field of the fan. The simulation result guides the optimal installation angle of the flow guide device. The installation angle of the upper deflector is 50°, and the installation angle of the lower deflector is 25°, so that the airflow generated by the air-assisted sprayer is mainly concentrated at a height of 0.7–3 m when it reaches the pear tree canopy. The installation angle of the inner deflector 1 and inner deflector 2 is 35°, the installation angles of the inner deflector 3, inner deflector 4, and inner deflector 5 are all 45°, and the average speed is increased by 18.81% in the range of height 1.6–2.4 m. A velocity distribution experiment is designed to measure the airflow velocity to verify the accuracy of the CFD simulation model. The simulation value is basically consistent with the measured value, which provides guidance for optimizing the parameters of the flow guide device.