Reservoir Destratification via Mechanical Mixers
Publication: Journal of Hydraulic Engineering
Volume 119, Issue 4
Abstract
Destratification techniques are often used to improve water quality in reservoirs. The majority of investigations have concentrated on the use of bubble aerators; however, an interesting alternative is the use of mechanical mixing systems consisting of a large propeller immersed in the water column. A laboratory study of such a system was used to examine the efficiency of energy conversion from mechanical energy to buoyancy flux as a function of impeller diameter, the speed of rotation, and the degree and type of stratification. The results were shown to depend on a generalized Froude number with the peak efficiency of energy conversion as high as 12%. A direct scaling mechanism enabling the results found in the laboratory model to be applied to a prototype situation was achieved via the application of derived scaling parameters. A simple design methodology for prototype versions of mechanical mixing systems based on this study is suggested.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 119 • Issue 4 • April 1993
Pages: 438 - 457
Copyright
Copyright © 1993 American Society of Civil Engineers.
History
Received: Mar 31, 1992
Published online: Apr 1, 1993
Published in print: Apr 1993
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