Abstract: The horizontal spray rod has wide spray and high efficiency, and a large number of users. However, the vibration of the boom caused by the chassis movement and other factors is the main cause of the droplet loss. In order to solve this problem, based on CFD, the spray flow field is established through the physical specification of the nozzle. When the horizontal boom is swinging, the effect of the rotation angle of the spray source on the droplet deposition level is adjusted in real time. The simulation results show that when the spray rod is swung, the spray source rotates counterclockwise; When the spray rod rises, rotate the spray source clockwise, and the deposition effect tends to be optimized without changing the rotation angle of the spray source. The best effects of the two adjustments are DV.9 value 43.2μm. Deposition density 108 particles/cm2, droplet size DV.9 is 47.3 μm. The deposition density is 118 particles/cm~2, and the change process is regarded as a linear change. It can be seen that adjusting the rotation angle of the jet source in real time plays a positive role in improving the droplet deposition effect; By calculating the deposition ratio of droplets in each state and carrying out regression analysis, it can be seen that when the spray rod has a large swing angle, the deposition effect of droplets is directly affected by the rotation angle; This research provides theoretical basis and data reference for the relevant scholars of precise spray control.