Browse > Article
http://dx.doi.org/10.17820/eri.2017.4.1.024

Numerical Simulation of Flow Characteristics and Channel Changes with Discharge in the Sharped Meandering Channel in the Naeseongcheon, Korea  

Jang, Chang-Lae (Department of Civil Engineering, Korea National University of Transportation)
Publication Information
Ecology and Resilient Infrastructure / v.4, no.1, 2017 , pp. 24-33 More about this Journal
Abstract
This study investigates the flow characteristics and bed changes with discharge using a two-dimensional numerical model, Nays2DH. The water depth at the outer part of curved channel is formed deeper from the narrow part after passing through the curved part. The point bar is developed in the wide section and water depth is shallow in the inside of the curved section. The flow is concentrated in the outer pater of the meandering section, which leads to the deep water. In the downstream section where the straight line formed, the flow is concentrated at the center of the bed. Alternating deep water and shallow places are generated due to the continuous formation of meandering. These characteristics are formed by the influence of strong two-stream flow in meandering stream. The dimensionless tractive force is also large in the region where the flow velocity is concentrated. However, in the narrow and sharp meandering river reaches, the pattern of bed changes and the spatial distribution patterns of flow velocity and dimensionless tractive force are inconsistent in the narrow and sharp meandered reaches due to the strong secondary flow.
Keywords
Bed change; Discharge change; Numerical simulation; Sharped meandering channel;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 Kang, K.-H., Jang, C.-L., Lee, G.-H. and Jung, K. 2016. Numerical analysis of the morphological changes by sediment supply at the downstream channel of Youngju dam. Journal of Korea Water Resources Association 49(8): 693-705. (in Korean)   DOI
2 Lee, K. S. and Jang, C.-L. 2016. Numerical investigation of space effects of serial spur dikes on flow and bed changes by using Nays2D. Journal of Korea Water Resources Association 49(3): 73-81. (in Korean)   DOI
3 Nanson, R.A. 2010. Flow fields in tightly curving meander bends of low width-depth ratio. Earth Surface Processes and Landforms 35(2): 119-135.   DOI
4 Schuurm, F., Shimizu, Y., Iwasaki, T. and Kleinhans, M.G. 2016. Dynamic meandering in response to upstream perturbations and floodplain formation. Geomorphology 253: 94-109.   DOI
5 Ashida, K. and Michiue, M. 1972. Study on hydraulic resistance and bedload transport rate in alluvial streams. Proceedings of the Japan Society of Civil Engineers 206: 59-69.
6 Blanckaert, K. 2011. Hydrodynamic processes in sharp meander bends and their morphological implications. Journal of Geophysical Research: Earth Surface 116(F1), doi:10.1029/2010F001806.   DOI
7 Cui, Y., Parker, G., Lisle, T.E., Gott, J., Hansler-Ball, M.E., Pizzuto, J.E., Allmendinger, N. and Reed, J.M. 2003. Sediment pulses in mountain rivers: 1. Experiments. Water Resources Research 39: 1239, doi:10.1029/2002WR001803.   DOI
8 Engel, F.L. and Rhoads, B.L. 2016. Three-dimensional flow structure and patterns of bed shear stress in an evolving compound meander bend. Earth Surface Processes and Landforms 41: 1211-1226.   DOI
9 Hickin, E.H. 1978. Mena flow-structure in meanders of the Squamish River, British Columbia. Canadian Journal of Earth Sciences 15(11): 1833-1849.   DOI
10 Iwasaki, T., Shimizu, Y. and Kimura, I. 2016. Numerical simulation of bar and bank erosion in a vegetated floodplain: A case study in the Otofuke River. Advances in Water Resources. http://dx.doi.org/10.1016/j.advwatres.2015.02.001.   DOI
11 Jang, C.-L. and Shimizu, Y. 2005. Numerical simulation of relatively wide, shallow channels with erodible banks. Journal of Hydraulic Engineering 131(7): 565-575.   DOI
12 Jang, C.-L. and Shimizu, Y. 2007. Vegetation effects on the morphological behavior of alluvial channels. Journal of Hydraulic Research 45(6): 763-772.   DOI