title: Optimum air-demand ratio for maximum aeration efficiency in high-head gated circular conduits.
abstract: Oxygen is an important component of water quality and its ability to sustain life. Water aeration is the process of introducing air into a body of water to increase its oxygen saturation. Water aeration can be accomplished in a variety of ways, for instance, closed-conduit aeration. High-speed flow in a closed conduit involves air-water mixture flow. The air flow results from the subatmospheric pressure downstream of the gate. The air entrained by the high-speed flow is supplied by the air vent. The air entrained into the flow in the form of a large number of bubbles accelerates oxygen transfer and hence also increases aeration efficiency. In the present work, the optimum air-demand ratio for maximum aeration efficiency in high-head gated circular conduits was studied experimentally. Results showed that aeration efficiency increased with the air-demand ratio to a certain point and then aeration efficiency did not change with a further increase of the air-demand ratio. Thus, there was an optimum value for the air-demand ratio, depending on the Froude number, which provides maximum aeration efficiency. Furthermore, a design formula for aeration efficiency was presented relating aeration efficiency to the air-demand ratio and Froude number.
authors.affiliation: Civil Engineering, Firat University, Elazig, 23119, Turkey.
authors.forename: Fahri
authors.initials: F
authors.lastname: Ozkan
authors.affiliation: Civil Engineering, Firat University, Elazig, 23119, Turkey.
authors.forename: M Cihat
authors.initials: MC
authors.lastname: Tuna
authors.affiliation: Faculty of Architecture and Design, Zirve University, Gaziantep, 27260, Turkey E-mail: ahmet.baylar@zirve.edu.tr.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Baylar
authors.affiliation: Civil Engineering, Firat University, Elazig, 23119, Turkey.
authors.forename: Mualla
authors.initials: M
authors.lastname: Ozturk
mesh_terms: D010100:Oxygen; D012044:Regression Analysis; D013696:Temperature; D014867:Water; D060753:Water Quality; D014881:Water Supply
chemical_list: D014867:Water; D010100:Oxygen