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http://dx.doi.org/10.3741/JKWRA.2014.47.11.1027

Numerical Analysis of Flow and Bed Changes due to Tributary Inflow Variation at the Confluence of the Namhan River and the Geumdang Stream  

Ji, Un (River and Coastal Research Division, Water Resources & Environment Research Department, Korea Institute of Civil Engineering and Building Technology)
Jang, Eun Kyung (River and Coastal Research Division, Water Resources & Environment Research Department, Korea Institute of Civil Engineering and Building Technology)
Publication Information
Journal of Korea Water Resources Association / v.47, no.11, 2014 , pp. 1027-1037 More about this Journal
Abstract
Flow and bed changes due to tributary inflow variation at the confluence of the Namhan River and the Geumdang Stream were analyzed in this study using a two-dimensional numerical model. As a result of the numerical analysis, the velocity downstream of the confluence was greater than the velocity upstream of the confluence in the main channel regardless of the magnitude of tributary inflow. However, as tributary discharge increased, the channel erosion was accelerated and the dry area was produced at the tributary. Due to the bed erosion at the tributary, sediment transport was increased and the eroded sediments were deposited in the confluence area. The deposition in the confluence area changed the flow direction at the main channel to the left side and the localized flow eroded the channel bed at the left side. Therefore, it is expected that bank failure due to continuous bed degradation is possible in this area.
Keywords
bed change; CCHE2D; numerical modeling; river confluence; tributary discharge;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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