Effect of Air Hole Diameter in Circular Conduits for Air Injection

The oxygen concentration in water is a prime indicator of the water quality for human life aquatic biota. The physical process of oxygen transfer or oxygen absorption from the atmosphere acts to replenish the used oxygen. This process is called re-aeration or aeration. Many hydraulic structures are used for aeration. Gated conduit aeration is a method of aeration that has become popular in recent years. In this study, the effect of air hole diameter in circular conduits for air injection was investigated. It is observed that increment in the diameter of air hole caused a rise in Qa/Qw. Additionally, results proved that the diameter of air hole plays an important role in the air injection of circular conduits. Moreover, a regression equation is obtained for air injection rate. For this aim, genetic expression programming, a recently developed artificial intelligence technique, is used. The model equation showed high correlation coefficient and low minimum square error value.