EVALUATING THE PERFORMANCE OF THE POP- UP SPRINKLER

This investigation was carried out at Faculty of Agriculture , Menoufia University, Egypt, on the Pop-Up sprinkler at operating pressures of 1.5 , 2 and 3bar, sprinkler emission angles of 45◦ , 90 ◦ ,135 ◦ , 180 ◦ ,225 ◦ , 270 ◦ , 315 ◦ and 360◦ and riser heights of 0.15 ,0.75 and 1.25 m . Discharge, uniformity distribution, coefficient of variation and water losses percent of the sprinkler due to evaporation and water drift were determined . Results indicated that, when pressure decreases, discharge and coefficient of uniformity decrease . The percentage of the average decreasing for discharge were 28 and 42% and decreasing of coefficient of uniformity were 12.05 and 23.77% when using the operating pressures of 2 and 1.5 bar compering with 3 bar resp. But increase coefficient of variation and water loss percent due to evaporation and water drift .Moreover, increasing the riser height at the sprinkler emission angles the discharge and the coefficient of uniformity decrease . When angle increase from 45o to 360◦ the discharge and coefficient of variation increase from o.115 to 0.362 m^3 /h and from 14.54 to 30.98 % resp. ,while coefficient of uniformity and water loss percent .decrease from 80.46 to 74.38 % and from 17.85to 11.21 % resp. Due to interaction between the operating pressure 3 bar and height riser of 0.15 m at emission angle of 360 ◦ gave the highest value of the discharge , while at the angle of 45 ◦ gave the highest value of coefficient of uniformity.