Hydraulic Studies of Different Microsprinkler

Five different microsprinklers having nozzles size of 1.12, 1.30, 1.50, 1.85 and 2.50 mm diameter were studied. The system was operated at the operating pressures of 0.5, 1.0, 1.5, 2.0 and 2.5 kg/cm² and for different spacing viz. 1.5 × 1.5, 2.0 × 2.0, 2.5 × 2.5 and 3.0 m × 3.0 m. A pressure discharge relationship was developed from the observed data. The nozzle size with 1.12 mm diameter exhibited logarithmic correlation in the form Q= a ln(X) + b, where the value of the coefficient ‘a’ was observed as 25.54 and the coefficient ‘b’ as 42.79. Where as a power correlation in the form Q= a X^b was observed for 1.30, 1.50 and 2.5 mm diameter nozzle. The value of the coefficient ‘a’ was found to be 75.54, 93.36 and 179.3, respectively. The coefficient ‘b’ was found to be 0.508, 0.474 and 0.557, respectively. The nozzle with 1.85 mm diameter exhibited linear equation in the form Q= a X + b, where the value of the coefficient ‘a’ was found as 51.55 and the coefficient ‘b’ as 63.52. The effect of microsprinkler spacing, operating pressure and nozzle size on the uniformity of the microsprinkler is discussed. The optimal spacing for operation of most of the microsprinklers was observed to be 1.5 m × 1.5 m under the operating pressure of 1.5 kg/cm². The manufacturer coefficient of variation for microsprinkler with 1.50, 1.85 and 2.50 mm nozzle size were found to be excellent. However, the manufacturer coefficient of variation for 1.12, 1.25 mm nozzle microsprinkler was observed within the acceptable limit.