With the effective use of aerators with low energy cost and high aeration performance, aquaculture areas can be developed and supported. The main objective of this study is to determine the optimal physical parameters of high aeration capacity high head conduits and to ensure low energy costs, thus to present a comprehensive review of its usability for pond aeration. In this study, a high-head gated conduit was used as the aeration unit. After obtaining the design that will maximize the aeration performance of the high-head gated conduit, a prototype model was developed to ensure its effective use in pond aeration. The parameters affecting the performance of this developed aeration system and the corresponding energy cost values were determined. According to the results, the most important parameters affecting the aeration performance are, respectively, flow rate, the opening of the gate, hydrostatic level, and jet plunge angle. In the optimal design, more than three times the unit volume of water circulating in the system is added to the system. The cost value of this operation in terms of energy was measured as 0.10 kWh/m³ air. The developed system was found to have significantly higher energy efficiency values compared to alternatives, based on specific energy consumption data.

This paper reports on an experimental study of the effect of tailwater depth on local scour downstream of stepped-chutes. Different tailwater conditions were tested to study the form of the scour for two gradations of non-cohesive bed material, various flow rates, chute angles, sill heights and step heights. Measurements were taken to obtain the scour hole profile in the equilibrium state of scour, the value of the maximum depth of scour, the location of the maximum scour depth, and the length of the scour hole. The present results indicate that maximum depth and area of scour are highly dependent on tailwater depth. Moreover, the maximum scour depth increases with increases in the discharge and the tailwater depth. It was also found that step geometry, stepped chute angle and the sill types of the stilling basin are very important parameters for scour hole and geometry. A comparison was made between the scour characteristics produced by different tailwater depths. Empirical correlations predicting maximum scour depth were developed. Hence, accurate equations for the maximum scour depth are introduced.

Climate change and global warming are expected to affect water resources management and planning, requiring adaptations to changing conditions. Therefore, it is very important, especially for decision-makers, to identify demand deficits due to less water availability with climate change that may occur in the existing water supply system in advance. FEHEM, a hydroeconomic optimization model of the integrated reservoir system of the Upper Euphrates Basin, which is the largest and main basin providing water flow to the Euphrates River, is developed. Using a 45-year historical hydrological dataset, water management and hydroelectric operations are evaluated with a linear programming model at monthly time steps. The effects of climate change on the Upper Euphrates Basin are evaluated under low and high carbon emission scenarios. According to the average of the different climate scenarios studied in the model, the average decrease in flows is 37.5%. With climate change, peak flows will occur about 1–2 months earlier on average. As a result of these hydrological changes, the total amount of energy production in the basin will decrease by about 54% and energy revenue by the same percentage.

The accurate estimation of long-term resource availability, as represented by discharge, is an essential component of hydropower constructions for generation capacity estimation as well as environment protection on ungauged river basins. Feasibility studies concerning decision-making for various types of items to be used in a hydropower plant on ungauged river basins are important in order to estimate the energy generation, the approximate cost of the project, and the required budget allocation. A feasibility study is necessary which evaluates the energy generation cost, investment and maintenance costs for hydropower projects. The purpose of this study is to analyze the technical feasibility of hydropower plant installations at ungauged sites. A case study is performed to illustrate this investigation. By means of the methodology presented in this research work, it will be possible to carry out sound and successful research to assess the economic feasibility of a hydropower project on ungauged river basins.