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Numerical analysis of lateral geomorphology changes by channel bed deposition and bank erosion at the river confluence section

합류부 구간에서의 하상퇴적과 하안침식에 의한 평면적 하도변화 수치모의

  • Received : 2015.12.28
  • Accepted : 2016.03.11
  • Published : 2016.05.31

Abstract

The confluence section of rivers forms complex flow pattern due to inflow discharge variation at the mainstream and tributary. Due to complex flow characteristics, bed change and bank erosion at the local section produce lateral geomorphology changes in rivers. In this study, bankline change by bank erosion and bed change were simulated using CCHE2D of 2-dimensional numerical model for quantitative analysis of lateral changes in the confluence section of South Han River and Geumdang Stream. As a result, bankline at the left-side channel of the mainstream was largely changed in the downstream section of the confluence compared to the upstream section. Also, bank erosion in the tributary was hardly occurred and bankline at the left-side tributary and right-side main stream moved to riverside land due to decreased velocity and deposition.

Keywords

Bank Erosion;Bed Change;CCHE2D;Numerical Modeling;River Confluence

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Cited by

  1. Analysis on the sediment sluicing efficiency by variation of operation water surface elevation at flood season vol.49, pp.12, 2016, https://doi.org/10.3741/JKWRA.2016.49.12.971
  2. Estimation of River Dredging Location and Volume Considering Flood Risk Variation Due to Riverbed Change vol.18, pp.3, 2018, https://doi.org/10.9798/KOSHAM.2018.18.3.279

Acknowledgement

Supported by : 국토교통부