Aeration Performance of Rectangular Planform Labyrinth Weirs
Publication: Journal of Environmental Engineering
Volume 126, Issue 5
Abstract
Maintenance of a high level of dissolved oxygen is important in natural rivers and in some water treatment processes. This can be enhanced by creating turbulence in the water. One method of producing such turbulence is via the overflow jets downstream of weir structures. The aeration characteristics of straight weirs have been measured and analyzed by a number of investigators. However, labyrinth weirs, which are cranked in planform, have received little attention in this respect. The aeration performance of a weir under a particular set of flow conditions is largely determined by the characteristics of the overall jet. The geometry of labyrinth weirs provides increased sill length and often results in the overfall jets colliding with each other, both of which may lead to increased aeration. A series of laboratory experiments were run on rectangular planform labyrinth weirs. These showed that, although detailed geometry of the weir was not important, the labyrinth weirs aerated significantly better than an equivalent straight weir, particularly at low drop heights.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 126 • Issue 5 • May 2000
Pages: 456 - 465
History
Received: Jul 20, 1999
Published online: May 1, 2000
Published in print: May 2000
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