Characterisation of the micro-tube emitters used in a novel micro-sprinkler

de Almeida, Ceres Duarte Guedes Cabral and Botrel, Tarlei Arriel and Smith, Rod J. (2009) Characterisation of the micro-tube emitters used in a novel micro-sprinkler. Irrigation Science, 27 (3). pp. 209-214. ISSN 0342-7188

Abstract

The microtube is a simple and cheap emitter that was widely used throughout the world in the early days of drip irrigation. Its length can be adjusted according to the pressure distribution along the lateral line and the discharge from the microtube can be adjusted by its length. This not only counters the pressure loss due to pipe friction but also makes it suitable for undulating and hilly conditions, where pressure in the lateral line varies considerably according to the differences in elevation. This is the major problem facing the designer, i.e., emitter flow changes as the acting pressure head changes. In this study, a novel micro-sprinkler system is proposed that uses microtube as the emitter and where the length of the microtube can be varied in response to pressure changes along the lateral to give uniformity of emitter discharges. The objective of this work is to develop and validate empirical and semi-theoretical equations for the emitter hydraulics. Laboratory testing of two microtube emitters of different diameter over a range of pressures and discharges was used in the development of the equations relating pressure and discharge, and pressure and length for these emitters. The equations proposed will be used in the design of the microsprinkler system, to determine the length of microtube required to give the nominal discharge for any given pressure. The semi-theoretical approach underlined the importance of accurate measurements of the microtube diameter and the uncertainty in the estimation of the friction factor for these tubes.


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Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Additional Information: Awaiting Author's version which may be deposited in accordance with the copyright policy of the publisher.
Depositing User: Prof Rod Smith
Faculty / Department / School: Historic - Faculty of Engineering and Surveying - Department of Agricultural, Civil and Environmental Engineering
Date Deposited: 18 Nov 2009 10:29
Last Modified: 20 Jul 2014 04:41
Uncontrolled Keywords: drip irrigation; emitters; microtube; microsprinkler
Fields of Research (FOR2008): 09 Engineering > 0906 Electrical and Electronic Engineering > 090605 Photodetectors, Optical Sensors and Solar Cells
09 Engineering > 0999 Other Engineering > 099901 Agricultural Engineering
07 Agricultural and Veterinary Sciences > 0799 Other Agricultural and Veterinary Sciences > 079901 Agricultural Hydrology (Drainage, Flooding, Irrigation, Quality, etc.)
Socio-Economic Objective (SEO2008): D Environment > 96 Environment > 9609 Land and Water Management > 960905 Farmland, Arable Cropland and Permanent Cropland Water Management
B Economic Development > 82 Plant Production and Plant Primary Products > 8298 Environmentally Sustainable Plant Production > 829805 Management of Water Consumption by Plant Production
Identification Number or DOI: doi: 10.1007/s00271-008-0135-y
URI: http://eprints.usq.edu.au/id/eprint/5546

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