FRESENIUS ENVIRONMENTAL BULLETIN, vol.30, no.7, pp.8532-8540, 2021 (SCI-Expanded)
In pesticide applications with worn nozzles, spraying parameters such as droplet size, spray angle and spray pattern distributions changes, and consequently the biological efficiency decreases. In this study; to determine the negative effect of worn nozzles, spray angle. flow rate, spray pattern distribution changes and coverage rate of three worn nozzles (ST110/02 nozzles, Lechler Co.) and one brand new reference nozzle (ST110/02 nozzle, Lechler Co.) were tested at three different spraying pressures (200, 300 and 400 kPa). In tests; flow rates, volumetric spray patterns and coverage rates were measured and compared with the brand new reference nozzle. Taken images were analyzed by the novel image processing program developed in Vision Assistant Software for determining the spray angles of both the reference and three worn nozzles. Nozzle flow rates, spray pattern distribution with variation coefficient and droplet homogeneities with Relative Span (R) were determined in order to compare spraying performances of the reference nozzle with worn nozzles. According to the comparing the results of the reference nozzle and worn nozzles; the highest flow rate difference was achieved with the Worn-C nozzle at 104.65% and 400 kPa pressure value, while the highest variation coefficient difference was determined with the Worn-C nozzle at 255.12% and 200 kPa pressure value. Whereas the highest difference in terms of spray angle was achieved with the Worn-B nozzle at 124.58% and 300 kPa pressure value, the highest Relative Span (R) difference was achieved in the Worn-C nozzle at 29.41% and 400 kPa spraying pressure.