Investigation of the relationship between aeration efficiency and dissolved oxygen concentration in different types of nozzles

Water is of great importance in terms of the continuity of the living life cycle. Due to the destruction of environmental awareness, contamination is observed in drinking and using water. As a result of pollution of the water, the amount of dissolved oxygen in the water decreases and its quality decreases. By increasing the amount of dissolved oxygen in the waters, the quality of the water should be increased and the natural life cycle should be maintained in a healthy way. The amount of dissolved oxygen in the water can be increased through aeration. Water jets, which are one of the hydraulic structures, play a very important role in aerating water and increasing the amount of dissolved oxygen. In the natural environment, water jets shorten this long process quite a lot, even though aeration takes place in the contact of water with air. In this study, the aeration performance of the jets was investigated using circular cross-sectional pressurized water jets, which are one of the hydraulic structures and provide high aeration efficiency, and the common nozzle with high oxygen transfer efficiency and air entrainment rate was investigated. The water jets used have different properties and are compared in terms of air entrainment and oxygen transfer. As a result, it was observed that the air entrainment rate increased with the increase in Reynolds Number in all nozzle lengths and this rate was the maximum value of 130000 Reynolds on average. Air entrainment rate and oxygen transfer efficiency increase in parallel, but oxygen transfer efficiency (OE) is high at small flow values. Accordingly, it was observed that the most suitable jet is a 4D nozzle type that is four times the diameter of the jet.