tailieunhanh - Determination of hydraulic performance of trickle irrigation emitters used in irrigation systems in the harran plain

Trickle irrigation systems’ efficiency depends on system uniformity, which is determined by water discharge uniformity from emitters. It is impossible to produce 2 identical emitters due to manufacturing variations. The manufacturer’s coefficient of variance is used as a measure of discharge variations of emitters. | Turk J Agric For 28 (2004) 223-230 © TÜB‹TAK Determination of Hydraulic Performance of Trickle Irrigation Emitters used in Irrigation Systems in the Harran Plain Halil KIRNAK* University of Harran, Agriculture Faculty, Irrigation Department, 63200, fianl›urfa - TURKEY Ergün DO⁄AN University of Harran, Agriculture Faculty, Irrigation Department, 63200, fianl›urfa - TURKEY S›dd›k DEM‹R University of Harran, Graduate School of Natural and Applied Science, 63200, fianl›urfa - TURKEY Sabri YALÇIN Göktepe Co., 63200, fianl›urfa - TURKEY Received: Abstract: Trickle irrigation systems’ efficiency depends on system uniformity, which is determined by water discharge uniformity from emitters. It is impossible to produce 2 identical emitters due to manufacturing variations. The manufacturer’s coefficient of variance is used as a measure of discharge variations of emitters. In this study, manufacturers’ reported discharge rates and coefficients of manufacturing variation (CVm) values were compared with test results for various types of in-line emitters manufactured by 4 different companies in Turkey. A total of 9 drip irrigation lines, comprising 7 non-compensating and 2 compensating emitters, were tested at 50, 100, 150, 200 and 250 kPa pressures. Non-compensating emitter types were not tested at 250 kPa. Compensating emitter exponents ranged from to while non-compensating emitters’ values varied between and . Test results showed that only 1 of the 7 non-compensating emitters and both compensating emitters had flow rates within ± 10% of manufacturers’ reported values. The t-test between manufacturers’ reported and measured mean flow rates at manufacturers’ reported nominal operating heads showed that there was no significant statistical difference at the α 15 excellent average marginal poor unacceptable Emitter exponents The emitter is the most important part of drip irrigation tubing. An emitter with a high degree of pressure compensation