Spray Nozzle Wear Effects on Droplet Population

Abstract

The wear rate of spray nozzles affects several factors. This study aimed to investigate the influence of spray nozzle wear rate on droplet characteristics, such as droplet size, droplet homogeneity, droplets prone to drift, and flow rate variation. Eight hydraulic nozzles models were subject to an accelerated wear test, and their effects were measured at six experimental wear times (0, 10, 20, 30, 40, and 50 hours). The following variables were evaluated: volume median diameter, percentage of spray volume containing droplets smaller than 100 μm (prone to spray drift), flow rate (L min -1 ), and relative span, which indicates droplet size homogeneity. The droplet population was measured using a laser particle size analyzer. The use of the spray nozzle tip influences the quality of the spray application due to the wear rate. This study revealed a linear increase in the flow rate and volume median diameter as functions of the wear rate increment. The droplet size increased over the wear time, which consequently modified the volume percentage of droplets smaller than 100 μm and significantly increased the relative span.

Control of Urochloa decumbens Using Glyphosate Applied by Remotely Piloted Aircraft and Ground Sprayer with Different Spray Nozzles

“…The RA indicates the homogeneity in the droplet size [ 45 ]. The lower the RA value is, the lower the amplitude between the values of the diameters of the droplets produced during spraying and, consequently, the better the quality of the application, as the process is more easily controlled.…”