Wadi Houran is one of the largest valleys in Iraq. Although it is discharging billions of rainfall water over/during many years to Euphrates river, it's almost devoid of agricultural investment. The current study aims to focus on this important valley water resource and study the possibility of constructing a series of small dams to store rainfall water and planting forestry and establishing a natural reserve that is able to sustain and improve ecology system. Target area of 4000 km2 is selected in the midstream of the valley. In general, it is about one billion m3 of rainwater flowing to Euphrates River during some years with yearly average values about 400 Mm3. Four dams were constructed to store about 46 Mm3 of rainwater. It is possible to construct small-dam-series of optimal height and location to expand the rainwater harvesting and groundwater recharging. A Current study was done and aimed to establish of oases and natural reserves in order to improve climate conditions, minimize the dust and CO2, mitigation of summer high temperature and decrease the soil erosion due to torrents. This study recommended constructing 13 optimal height dams that store about 303 Mm3 of water, and increase the water surface area of reservoirs in this valley from 15 to 90 km2which leads increase the water volume that is recharging ground water from 4.7 Mm3 to 28 Mm3 per year.
In recent years, Iraq suffers from exacerbation of the deficit of electrical energy as well as the great environmental pollution resulting from the use of traditional fuels. This called for serious thought to search for using clean and renewable energy sources may available in Iraq.In the present study; small hydropower (i.e. Archimedes screw turbine) are specifically used with a low head at Ramadi Barrage in Iraq. This type of small hydropower station is suitable to apply because not need high storage water or high head in Barrage. The power production in this technology depends on the parameters of the location in which it is placed such as (length L, angle of inclination α, Diameter D,….). The physical model of the Archimedes screw turbine is applied to determine the optimal α. The solid work package with a combination of Computational Fluid Dynamics (CFD) analysis by ANSYS have been used to simulate numerically a three dimensions model to determine the value of power that could be produced by the Archimedes turbine in the Ramadi Barrage. The turbine's performance are tested on two cases which represent low and high discharge investigations with different α (18⁰, 23⁰, 30⁰, 35⁰) based on different flow conditions and different water head between upstream and downstream of the barrage. The results showed that the maximum power production from the barrage is 280,000 watts with α=35° and efficiency η=89.9% for case 1; while; this power becomes 400,000 watts with α=30° but of efficiency η=84.9% for case 2. It is concluded from this research that power production from Ramadi Barrage could be investment to eliminate the deficit in the electrical energy in Iraq.
The spillway is an important structure in the dams, used to pass the flood wave to the downstream safely. In the past decades, Computational fluid dynamics (CFD) has evolved. Research findings have shown the CFD models are a great alternative for laboratory models. According to it, the flow pattern over ogee spillways can be studied in a short time and without paying high expenses. Because the flow over the ogee spillway is turbulent and has a free surface, its properties are complex and often difficult to predict. Therefore, the present paper focuses on the study of turbulence closure models including the standard k-ε, RNG k–ε, k–ω, also, the large-eddy simulation (LES) models, to assess their performance to simulate flow over the spillway. The Flow-3d software with the volume-of-fluid (VOF) algorithm is applied to obtain the free surface for each turbulence model. The results of the analysis show that the LES model yielded better results when compared with laboratory results, while the turbulence closure models result of Reynold average Navier Stocks equations (RANS) was more stable, especially standard k-ɛ and RNG models.