Predicting spray drift reduction classification of flat-fan nozzles based on droplet size spectrum

Spray drift reduction classification evaluation provides theoretical support and technical basis for chemical precision applications. Traditional measurement of spray drift reduction relies on the wind tunnel experiment, which involves a complex testing process and a long measurement cycle. In this study, the feasibility of using a droplet size spectrum to implement drift reduction classification of flat-fan nozzles was studied. A phase doppler interferometry (PDI) was used to determine the droplet size spectra of seven types of flat-fan nozzles, including D_V50, V₇₅%, V₁₀₀%, V₁₅₀%, and V₂₀₀%, and the calculated drift reduction classifications were compared with the measurements obtained by the wind tunnel method. The results showed that droplet-spectrum-based spray drift potential reduction classification was highly correlated with the results obtained from the wind tunnel method, with the lowest correlation coefficient being 0.969. Spray drift potential reduction classification represented by V₂₀₀% shows the highest consistency with the wind tunnel measurements. This study confirms the positive potential of using droplet size spectra to estimate spray drift, and provides a method for the classification of agricultural nozzles.