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http://dx.doi.org/10.3741/JKWRA.2014.47.1.37

Numerical Experiments of the Behavior of Bars in the Channels with Periodic Variable Width  

Jang, Chang-Lae (Dept. of Civil Engineering, Korea National University of Transportation)
Publication Information
Journal of Korea Water Resources Association / v.47, no.1, 2014 , pp. 37-47 More about this Journal
Abstract
This study examines the processes and the behaviour characteristics of forcing bars in channels with periodic variable width in the alternate and braided regimes by using a two dimensional numerical model. The wavelength and the migration speed decrease as the amplitude of variable width increases. The forcing effects of the width variation on the alternate bars is stronger than those on the braided bars. The bar migration speed increases as the dimensionless amplitude in the braided regime is 0.25. However, the migration speed is abruptly decreased as the amplitude in it was larger than 0.25. The bar migration speed increases in the alternates bar regime as the dimensionless wavelength increases. However, the migration speed decreases around 1 of the wavelength. As the bar wavelength and the variable width wavelength coincide, the bars don't migrate downstream by the strong forcing effects on the bars due to the suppression by the width variation.
Keywords
morphological changes; periodic width variation; numerical model; free bars; forced bars;
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Times Cited By KSCI : 1  (Citation Analysis)
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