Determining hydraulic characteristics in laterals and drip irrigation systems

Diego Chamba, Sergio Zubelzu and Luis Juana

Agricultural Water Management, 2019, vol. 226, issue C

Abstract: Evaluation methods for functioning drip irrigation units are proposed to determine the hydraulic characteristics of emitters and pipelines. The aim of the study was to characterize the discharge curve of the emitters, their coefficient of variation, and the head losses in laterals and submains. In the laboratory, four laterals were tested under a wider range of pressure heads than the typical values of field installations. In additional, a field irrigation unit was evaluated. The discharge curve and coefficient of variation were determined in the unit with an accuracy similar to that obtained from laboratory experiments. For self-compensating emitters, a constant flow rate above the lower limit of the compensating range and an orifice-type discharge curve below that limit are proposed. For non-compensating emitters, an orifice-type discharge curve, with exponent x = 0.5, except for specific cases, is proposed. The manufacturing coefficient of variation was independent of pressure and relatively low for all the analysed emitters. Regarding the parameters of the local head losses, the equivalent length le presented values more independent of the flow than coefficient K. For the characterisation of laterals with self-compensating emitters, it is recommended to measure with the downstream end open to reduce the uncertainty in the experiments. The results show that the unit can be operated so that the average discharged flow and the uniformity can be matched just controlling the pressure head at upstream end point of the unit.

Keywords: Drip irrigation; Evaluation; Hydraulic characterisation; Emitter discharge; Head loss (search for similar items in EconPapers)
Date: 2019
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0378377418318912
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:agiwat:v:226:y:2019:i:c:s0378377418318912

DOI: 10.1016/j.agwat.2019.105791

Access Statistics for this article

Agricultural Water Management is currently edited by B.E. Clothier, W. Dierickx, J. Oster and D. Wichelns

More articles in Agricultural Water Management from Elsevier
Bibliographic data for series maintained by Catherine Liu ().