A. H Nasrolahi, M. Behzad, S. Bromand Nasab, M. Heydariniya,
Volume 17, Issue 66 (2-2014)
Abstract
Drip irrigation is a new method of irrigation that is rapidly growing in different countries. The emitters are the most important parts of a drip irrigation system. Many factors such as physical, chemical and biological clogging, pressure, water temperature affect the emitter´s uniformity of water emission. In this study, to investigate pressure effect on the hydraulic performance of emitters, 7 kinds of compensating emitters in the market were selected and studied in laboratory conditions. For this purpose, a drip irrigation system was designed in irrigation laboratory in faculty of water sciences engineering, Shahid Charm University, Ahwaz. Average flow of emitters, Manufacturer´s coefficient of variation of emitter(CV), emission uniformity(EU), Christiansen coefficient of uniformity(CU) and Flow Variations for all types of emitters at pressures of 5, 10, 15 and 20 meters were calculated and compared. Also, in order to compare the pressure compensating capacity, for every emitter the equation of Flow- pressure was extracted. Results showed that the D-type emitter has the best hydraulic performance from among the emitters tested. Therefore, to achieve higher efficiency and also to use it on slopes and uneven lands this emitter is recommended as the best. However, performances of other emitters are also acceptable.
F. Gavazi, E. Maroufpoor,
Volume 21, Issue 1 (6-2017)
Abstract
The main purpose of this study is investigation of hydraulic properties in drip irrigation tape. In this study, 10 types of drip irrigation tape were tested, and the effect of 4 temperatures of water, 13, 23, 33 and 43 °C, was investigated according to the standard ISO 9261 and ISO IRISI. Initially all experiments were performed in standard temperature (23°C) in order to obtain qualitative evaluation indexes of tapes. The results obtained were as follows: According to the Cv, 8 models of tapes were ranked as good and 2 models as medium. According to the difference between the actual and nominal flow rates, 3 models were ranked as good, 3 models as medium, 3 models were acceptable and 2 models were unacceptable. According to the EU, 9 models were ranked as excellent and T3 was ranked as good. According to the UC, UC of all models was more than 70% and their flow rate variation follows normal distribution. According to qvar, flow rate changes in 3 models were acceptable, 2 models were ranked as good and 5 models were unacceptable.
