Turbulent Boundary Layers in Vertical Curves
Publication: Journal of Hydraulic Engineering
Volume 114, Issue 7
Abstract
Cavitation damage is often observed near the downstream end of the flip buckets of many high‐head outlet works. To analyze and mitigate the problem, many research efforts now focus on the development of the boundary layer along the bucket surface. In this paper, the centrifugal‐force effect on flow characteristics over a bucket is discussed. The boundary‐layer momentum and energy integral equations are derived by incorporating the effect of the bucket curvature. The surface shear stresses are calculated based on the theory of wall layers. The turbulent boundary‐layer thickness and the exponential velocity distribution are obtained by applying the finite‐difference method. It was found that higher velocity occurs near the bucket surface throughout its entire length, and the skin‐friction coefficient increases significantly in the downstream half of the bucket. The cavitation inception number approaches its maximum value at the end of the bucket, and, therefore, cavitation damage is most likely to occur near the downstream end of the flip bucket of high‐head outlet works.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 114 • Issue 7 • July 1988
Pages: 783 - 797
Copyright
Copyright © 1988 ASCE.
History
Published online: Jul 1, 1988
Published in print: Jul 1988
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