Reduced span spray: Part 3: Design of a narrow span nozzle

Optimisation of the droplet spectra of the agricultural spray may increase the spray application efficiency. The optimal spray would contain only the most efficient droplets in term of speed and size. Therefore, this paper is presenting the first steps of the design of a narrow span nozzle in order to produce an optimised spray. The starting geometry is a splash plate nozzle with a disk ending with structures (i.e. tooth, grooves, and needles) that would separate the liquid sheet into jets. These jets would be in the Rayleigh regime which has the advantage of producing narrower droplet spectra than liquid sheet break-up. The present project aims to design a hydraulic nozzle producing a spray with a narrow drop size distribution in order to increase the agricultural spray application efficiency. In the present paper the first project steps are presented.