Effect of strainer type, spray pressure, and orifice size on the discharge coefficient of standard flat-fan nozzles

Abstract

IntroductionFlat-fan spray nozzles are widely used nozzle types in pesticide applications. The nozzle orifice, which is rectangular or oval-shaped, is located in the middle of the V-shaped channel on the nozzle body. The spray angles of these nozzles are manufactured with eight different color codes ranging from 65° to 120°. Flow rates of these nozzles are mainly affected by the function of the orifice size and spray pressure, which are the variable parameters. The nozzle flow rate, which is one of the most important measure parameters after manufacturing, is an indicator of nozzle quality. The flow rate at spray pressure of 276 kPa (40 psi) of a nozzle manufactured with different color codes and orifice sizes has been standardized by the ISO International Standards (ISO, 1996) and the American Society of Agricultural and Biological Engineers Standards (ASABE Standards, 2009). According to hydraulic principles, the flow rate of a nozzle is proportional to the square root of spray pressure. This means that the exponent coefficient of spray pressure is 0.50. This is commonly applied to all nozzles, but it is in fact erroneous to do so. In particular, nonspiral design full cone nozzles and wide angle full cone nozzles have an exponent of 0.46 or 0.44 (Spraying Systems Co., 2014). This information indicates that the flow characteristics of a nozzle depend on its design attributes.Sayıncı (2014) determined that the nozzle strainers lead to change in the pressure exponent coefficient, which is the relation between flow rates and spray pressures of spray nozzles. The exponent coefficient ranged between 0.48 and 0.49 for the nozzles used with standard types of nozzle strainers, and between 0.55 and 0.57 for the nozzles used with ball check strainers.Nozzle strainers, which are a crucial part of a sprayer, are located in the nozzle body to screen out the debris

Discharge Coefficients of Flat Fan Nozzles

“…As shown in table 6, there were minimal differences in measured discharge coefficients for the air-induction nozzles with water and with the chosen surfactant solution.We can compare our results with previously reported values in the literature. Sayinci (2015b) reported the same trend of C d decreasing with increasing pressure (with the exception of when a ball check valve is used). There was no clear trend in his data for change in C d with orifice size.…”

“…Most of the reported measurements of discharge coefficient reported in the literature are those by Sayinci (2015aSayinci ( , 2015b and Sayinci and Kara (2015), as well as the measurements by Womac and Bui (2002) and Zhou et al (1996). In research where droplet velocities have been measured at the location of sheet breakup, such as with PIV, those velocities can be used to calculate the discharge coefficient as well.…”

Droplet Kinematic in Hollow Cone Polyacetal (POM) Sprayer Nozzles

“…Her bir meme plakasında renk, slot sayısı veya malzeme özellikleri farklı 4 çeşit girdap plaketi (mavi, 2-slot, POM; kahverengi, 3-slot, POM; sarı, 2-slot, POM; paslanmaz çelik, 2-slot) kullanılmıştır. Pülverizatör memeleri için süzgeçler, akış karakteristiğini değiştirdiğinden (Sayıncı ve Kara 2015;Sayıncı 2014;Sayıncı 2015;Sayıncı 2016) 0.084±0.006 a 0.084±0.009 a 0.078±0.008 a 0.082±0.008 a 0.077±0.006 a F değeri (p, sigma) 37.22 (0.000)** 24.74 (0.000) 24.52 (0.000) 30.62 (0.000) 32.86 (0.000) Ø1.2…”

Effect of Swirl Plates on Volumetric Discharge Rate and Spray Characteristics of Hollow Cone Nozzles

“…In the present study, all measurements were performed without using a strainer. As the strainers were known to alter the flow characteristics of the spray nozzles (Sayıncı and Kara, 2015;Sayıncı, 2014;Sayıncı, 2015;Sayıncı, 2016), the nozzle discharge rate and other measurements were performed specific to this study. In conclusion, the swirl plates on the nozzle discs with small orifice diameter have a significant impact, and the effect of the swirl plates on the discharge rate variation gradually decreased as the orifice diameter increased.…”

“…In terms of the nozzle material, Sayıncı et al (2013) found that the discharge coefficient of polyacetal (POM) nozzle discs was lower than those of ceramic and stainless steel. In terms of the nozzle type, the discharge coefficient ranged between 0.85-0,98 for standard flat fan nozzles (Sayıncı and Kara 2014;Sayıncı, 2015;Zhou et al, 1996;Cloeter et al, 2010;Dorr et al, 2013); 0,67-0,77 for preorifice chamber flat fan nozzles (Sayıncı and Kara, 2015); 0,38-0,43 for air-induction flat fan nozzles (Cloeter et al, 2010;Dorr et al, 2013).…”