The effect of cross-section and gated geometry on the air demand efficiency in the head conduits

The water is indispensable to balance the ecology and functionality of creatures. Hence, water has been used for drinking water supply, irrigation, and various industrial purposes. In the historical process, we are confronted with the "global water crisis" due to the population increase, urbanization, increasing water consumption with industrialization, environmental pollution caused by mixing of waste water to the nature, inadequacy of infrastructure and excessive irrigation in agriculture. The effectively use of freshwater bodies has crucial importance due the limited amount of freshwater sources. Thus, it is vital to improve the properties of polluted freshwater to reuse. The dissolved oxygen concentration is a crucial indicator for continuation of live on the water. In order for the dissolved oxygen concentration to reach the optimum value, the oxygen in the atmosphere must be brought into the water. In this direction, different flow systems with pressure and free surface for aeration have been widely used in recent years. In this study, the aeration efficiency of the high head gated conduits which can be an alternative to the existing aeration systems for aeration in water engineering was examined considering different cross-sectional types, gate opening ratios, conduit lengths and gate shapes. More than 1000 air demand ratio were measured by creating 144 different test series on one experimental setup. Experimental results have shown that high head gated conduits can be used efficiently for the aeration of water. In addition, the air demand ratio have been greatly increased by reaching the purpose of the thesis study.