PERFORMANCE ASSESSINGOF IMPACT AND ROTATING SPRINKLER BASED ON CATCH-CAN DATA

The main objective of the present study is to evaluate two types of sprinklers (impact sprinkler and rotating sprinkler), impact sprinkler (average nominal discharge from 780 to 1660 ℓ/h at operating pressure from 100 to 400 kPa) and rotating sprinkler (average nominal discharge from 360 to 730 ℓ/h at operating pressure from 50 to 350 kPa) to determine optimum operating conditions that achieve high application uniformity. The coefficient of uniformity (CU) and distribution uniformity (DU) were evaluated under different levels of operating pressure and constant riser height of 1.0 m. It was concluded that the operating conditions that achieved high coefficient of uniformity and distribution uniformity was operating pressure of 200 kPa for impact sprinkler. The results showed that the highest values of CU and DU were 90.55 % and 68.10 % for impact sprinkler respectively while for rotating sprinkler with combination of trajectory angles (20o, 25o), the corresponding values of CU and DU were 85.60 % and 60.50 %, respectively. Also, to achieve high percentage of overlap simulation model was used, it appeared that the spacing between sprinklers should be higher than or equal to 50 % of wetted diameter to avoid water lose and minimize irrigation system cost.