Fator de atrito em tubos de polietileno de pequenos diâmetros
Cardoso, G.G.G. Frizzone, J.A. Rezende, R.
Fator de atrito em tubos de polietileno de pequenos diâmetros Friction factor for small diameter polyethylene pipes
On this paper, the results of an experimental study on the hydraulic friction loss for small-diameter polyethylene pipes are reported. The experiment was carried out using a range of Reynolds number between 6000 to 72000, obtained by varying discharge at 20oC water temperature, with internal pipe diameters of 10.0 mm, 12.9 mm, 16.1 mm, 17.4 mm and 19.7 mm. According to the analysis results and experimental conditions, the friction factor (f)of the Darcy-Weisbach equation can be estimated with c = 0.300 and m = 0.25. The Blasius equation (c = 0.316 and m = 0.25)gives an overestimate of friction loss, although this fact is non-restrictive for micro-irrigation system designs. The analysis shows that both the Blasius and the adjusted equation parameters allow for accurate friction factor estimates, characterized by low mean error (5.1%).
EQUIPAMENTO AGRÍCOLA
MODELO MATEMÁTICO
IRRIGAÇÃO
POLIETILENO
PERFORMANCE
Fator de atrito em tubos de polietileno de pequenos diâmetros Friction factor for small diameter polyethylene pipes
On this paper, the results of an experimental study on the hydraulic friction loss for small-diameter polyethylene pipes are reported. The experiment was carried out using a range of Reynolds number between 6000 to 72000, obtained by varying discharge at 20oC water temperature, with internal pipe diameters of 10.0 mm, 12.9 mm, 16.1 mm, 17.4 mm and 19.7 mm. According to the analysis results and experimental conditions, the friction factor (f)of the Darcy-Weisbach equation can be estimated with c = 0.300 and m = 0.25. The Blasius equation (c = 0.316 and m = 0.25)gives an overestimate of friction loss, although this fact is non-restrictive for micro-irrigation system designs. The analysis shows that both the Blasius and the adjusted equation parameters allow for accurate friction factor estimates, characterized by low mean error (5.1%).
EQUIPAMENTO AGRÍCOLA
MODELO MATEMÁTICO
IRRIGAÇÃO
POLIETILENO
PERFORMANCE