Capped Water Intakes in a Stratified Crossflow
Publication: Journal of Hydraulic Engineering
Volume 115, Issue 2
Abstract
Tests are conducted on capped and uncapped circular intake holes in the bed of a flume, to determine the intake flowrate at which the upper layer of a stratified crossflow begins to be drawn into the intake. Equations are developed which predict the start of upper layer withdrawal as a function of crossflow and intake parameters. When the intake flowrate is increased above this inception level, the percentage of upper layer water in the intake flow increases, and then levels off to a limiting value. For the capped intakes, this limit always corresponds to selective withdrawal from the lower layer, but some of the uncapped intakes selectively withdraw from the upper layer in this limit condition. This confirms the value of a cap for promoting selective withdrawal from the lower layer. The tests are restricted to one value of the upper to lower layer depth ratio, but this value (0.25) is typical of many large cooling‐water situations. Flow patterns in the wake of a capped intake are investigated and related to the inflection points in the intake temperature graph.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 115 • Issue 2 • February 1989
Pages: 228 - 242
Copyright
Copyright © 1989 ASCE.
History
Published online: Feb 1, 1989
Published in print: Feb 1989
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