Location: Application Technology Research
Project Number: 5082-21620-001-028-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2024
End Date: Aug 31, 2025
Objective:
Develop and validate a completed computer prediction program that will be used on sensor-guided variable-rate intelligent sprayers to assist decisions on the pesticide spray application under uncontrollable weather conditions to improve spray application efficiency and reduce undesirable pesticide toxicity to the environment.
Approach:
A large computational domain using a supercomputer by cooperator will be established for the simulations of air flow distributions and droplet trajectories discharged from sensor-guided variable-rate sprayers. Win velocities, air jets, and droplet distributions will simulate by new methods. Trees will be modeled by setting porosity at structured cells where imaginary plants are assumed to be located. Source terms for momentum loss and changes of turbulence kinetic energy and specific dissipation rate due to the crops will be added to the governing equations within the cells of virtual crops. During the simulation, droplet trajectories will be recorded and saved in files which include the location, mass, diameter, velocity and number of droplets deposited on the ground, captured in the canopy, and travelling as spray drift. The amount of vaporized mass of droplets and their locations will also be recorded. The amount of spray deposits within the sprayed plants and amounts of airborne drift and ground deposits at different distances away from the sprayed row will be calculated and reported. The program prediction accuracy will be validated in apple orchards, nurseries and vineyards following standard test procedures. Laser-guided variable-rate sprayers equipped with hollow-cone nozzles will be used for the validation tests. Spray deposition samples will be collected and analyzed at different positions inside canopies, and at different heights from ground at different distances from the sprayed tree row. The amounts of spray deposits on all samples will be compared with the predictions. After the field test validation, the computer program will be integrated into the sensor-guided intelligent sprayers to assist decisions on scheduling pesticide spray applications for specialty crops under specific weather conditions that pesticides can be safely applied. Data generated by the program will also be used.
