Asymmetric Flow in Symmetric Expansions
Publication: Journal of the Hydraulics Division
Volume 108, Issue 10
Abstract
Asymmetric flow patterns may occur in perfectly symmetric abrupt expansions, in which the main flow deflects and attaches arbitrarily to one wall of the expansion. With the notable exception of fluidic devices, asymmetric flow patterns are detrimental in most civil engineering applications. The adverse effects include lengthening of the distance to full-width flow in expansions, inefficient operation of screens in screen channels, and increasing the potential for vortexing in pump intakes. No good explanation or prediction of the onset of asymmetric flow patterns is known to exist. This paper attributes the asymmetric behavior to a static instability of the system occurring under certain conditions of expansion geometry. The stability is investigated by analyzing the forces acting on the system when it undergoes a small deflection from its symmetric position. A mathematical stability criterion is developed and applied to subcritical, horizontal, rectangular expansions. The results are in excellent agreement with experimental observations (limited to small Froude Numbers). The predictive method is extended theoretically to the analysis of certain preventive and corrective measures. Means of extending the analyses to more complex two-dimensional and three-dimensional configurations are examined.
Get full access to this article
View all available purchase options and get full access to this article.
Information & Authors
Information
Published In
Journal of the Hydraulics Division
Volume 108 • Issue 10 • October 1982
Pages: 1082 - 1101
Copyright
© 1982 American Society of Civil Engineers.
History
Published in print: Oct 1982
Published online: Feb 3, 2021
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.