Hydraulic Analysis of Irrigation Network for the Proposed Taq-Taq Dam Using EPANET Software

Analysis of the pipe network aims to determine the pressure drops and flow rates in the individual parts of the network. In this study, the EPANET software was used for automatically solving problems of the network. The main objective of this study is to analyze the irrigation network of the proposed Taq-Taq dam using hydraulic simulation software. In order to study the distribution of pressure, velocity and head on the pipe network to ensure the operation of the network efficiently and improve quantity of water distributed through the pipelines system. The study explained the velocity, pressure, and head distributions along the pipeline of the proposed irrigation project. The results concluded that the simulated model seems to be reasonably close to those of an actual network system. KeywordsEPANET, Pipe flow, Pipe Network, Simulation, Water Demand. How to cite this article: I.R. Karim and S.A. Sahib, “Hydraulic Analysis of Irrigation Network for the Proposed Taq-Taq Dam Using EPANET Software,” Engineering and Technology Journal, Vol. 37, Part A, No. 10, pp. 429434, 2019.


Introduction
The aim is to introduce EPANET to model an irrigation network, and to solve any attached problems to an irrigation system. The model contains an optimization technique of network solver EPANET used to reach the proposed scheme. EPANET is chosen due to handle together steady state as well as extend period simulation network of water distribution. This chapter shows discussions the EPANET simulation model by using a sample model of a real irrigation system and sprinkler irrigation system [1]. An irrigation system can be defined as a hydraulic infrastructure that conveys water from the source to the consumers; it consists of five elements: pumps, pipes, valves, tanks, and reservoirs.

Description of Project
The purpose of the proposed Taq-Taq Dam is irrigation, hydroelectric power generation and flood control for downstream area. Besides serving the regulating dam for waters released of Dokan Dam power station. The proposed Taq-Taq Dam and Irrigation Project comprise six irrigation systems as shown in Figure (1). These systems are: Taq-Taq irrigation system, Kara Cuge irrigation system, Kanibi irrigation system, Haraba irrigation system, Kotan irrigation system, and Kasgah irrigation system [2]. The Kara Cuge irrigation system project was selected as a case study. The system receives water from a reservoir that has a capacity of 5292 m 3 and connected to the bottom outlet of the proposed Taq-Taq Dam with GRP (Glass Reinforced Polyester) this pipeline (C) Ø700mm dragged that has the length of 3464 m. The main supply line for system is divided into three directions: The first is the GRP pipeline (C-1), (Ø300mm, Ø250mm, and Ø150mm) at a total length of 2047 m. The second is the GRP pipeline (C-2) Ø300mm, and Ø100mm has a length of 1583 m. The last direction is also the GRP pipeline (C-3) within four pipes (Ø600 mm, Ø500 mm, Ø400 mm, and Ø300 mm) and 3933 m is the total length and it go under the bed of the river. Since terrain altitude is not higher than 380 meters above sea level (m.a.s.l) [2], working pressure is assured on entire irrigated area. Figure  (2).

I. EPANET software description
Pipeline network of the irrigation network was analyzed using EPANET software, which performs the behavior of water quality within a pressurized pipe hydraulic analysis engine which contains the following capabilities [4]: › Places no limit on the dimension of the network that analyzed › Computes head loss of friction by using either Darcy-Weisbach, Hazen-Williams, or Chezy-Manning equations › Contains minor head losses for fittings, bends. › Variable speed pumps or models constant › Computes cost as well as pumping energy › Models different types of valves › Allows the tanks of storage to have many forms (i.e., the diameter that changed with the height) › Considers a different demand for categories at every node, with its pattern of time variation. › Models pressure dependent on flow issuing of emitters. › Can base system operation on both timer controls and simple tank level, and complex rule based controls.
EPANET's simulation model computed the hydraulic heads at junctions and flow rates through links for a fixed set of tank levels, reservoir levels, and water demands over a succession of points in networks and extended period simulation of hydraulic. A network contains pipes, pumps, nodes (pipe junctions), valves and the reservoirs. EPANET tracks the water flow in every pipe, the pressure at every node; the water height in each reservoir, as well as the concentration of chemical species throughout the network during simulation interval included multiple time steps [3]. In addition, chemical species, source tracing and water age have been simulated. Running beneath Windows, EPANET supplies an integrated environment for input data of editing network, water quality simulations and running hydraulic, as well as the results are shown in formats variety. These include data tables, time series graphs, and colorcoded network maps in addition to contour plots.

II. Application the EPANET
The irrigation project for the study area was divided into two main sections through two main pipes from Reservoir (R-1). Each pipe is a 700mm diameter and distributes water to secondary pipes in both sides to deliver water to all parts of the irrigation project, as shows in Figure 3

Conclusions
i. In this paper, the researcher succeeded in modeling the water distribution system using EPANET2.0 software as a tool for improving the simulation of the hydraulic behavior of the water supply distribution network. After analyzing the water distribution network of the proposed Taq-Taq dam, we can obtain any value of variables. ii. A Comparison of the results that the researcher obtained indicates that the simulated model seems to be reasonably close to the same network.