University of Khartoum

Evaluation of Effects of Drip Irrigation System Lateral Line Lengths on Friction Losses and Hydraulic Performance under Field Conditions

Evaluation of Effects of Drip Irrigation System Lateral Line Lengths on Friction Losses and Hydraulic Performance under Field Conditions

Show full item record

Title: Evaluation of Effects of Drip Irrigation System Lateral Line Lengths on Friction Losses and Hydraulic Performance under Field Conditions
Author: Mohamed, Asma Awad Ali
Abstract: This study was conducted during the period from November 2015 to March 2016. The objective was to evaluate the effect of lateral lines length on friction losses and hydraulic performance of drip irrigation system under different operating pressures. A drip irrigation system was designed and installed in the Demonstration Farm of the Faculty of Agriculture, University of Khartoum at Shambat. The parameters considered were friction losses, coefficient of uniformity (Cu%), distribution uniformity (Du%), scheduling uniformity (Su) and discharge variations in the lateral lines. Friction losses were determined using Hazen-William’s equation. Lengths of lateral lines used were 20, 40 and 60 m. The inside diameter of the lateral lines was 13 mm. On-line ‘Turbo’ emitters were used in all laterals under three operating pressures of 0.75, 1.00 and 1.25 bar using a split-split plot experimental design. Each treatment was replicated three times. The SAS statistical package was used to analyze the data. Friction losses values for the 60 m long lateral line under the three operating pressures were significantly higher (P ≤ 0.05) than the values obtained for the 20 and 40 m lateral lines. The length of lateral line and the operating pressure significantly (P ≤ 0.05) affected the uniformity coefficient (Cu%) and the distribution uniformity (Du%). The highest Cu% value (96%) was obtained under operating pressure of 1.25 bar for the 20 m lateral line length, while the lowest value (71%) was obtained under 0.75 bar operating pressure for the 60 m lateral line length. The Du% values followed the same trend. For all laterals the highest values were obtained under 1.25 bar operating pressure and the lowest values were recorded under 0.75 bar operating pressure. The Cu% and Du% values for the 60 m length of lateral lines under the three operating pressures were significantly lower (P ≤ 0.05) than the values obtained for the 20 and 40 m long laterals. The scheduling uniformity was found to be 1.3 or less for the 20, 40 and 60 m length of lateral lines under the three operating pressures. Discharge variations along the lateral lines were found not to be significantly different under the three different operating pressures, falling within the allowable range. The results revealed that length of lateral lines acceptability excellent in 20 m and 40 m, and good in 60 m under 1.25 bar operating pressure. The study concluded that lateral lines length of 60 m or less can be used in drip irrigation system under 1.25 bar operating pressure without significant effects regarding friction losses, uniformity coefficient, distribution uniformity, scheduling uniformity and discharge variations.
URI: http://khartoumspace.uofk.edu/123456789/24154


Files in this item

Files Size Format View

This item appears in the following Collection(s)

Show full item record

Share

Search DSpace


Browse

My Account