Physical complexity to model morphological changes at a natural channel bend
journal contributionposted on 2016-10-13, 12:57 authored by Mingfu Guan, N.G. Wright, P.A. Sleigh, Sangaralingam Ahilan, R. Lamb
This study developed a two-dimensional (2-D) depth-averaged model for morphological changes at natural bends by including a secondary flow correction. The model was tested in two laboratory-scale events. A field study was further adopted to demonstrate the capability of the model in predicting bed deformation at natural bends. Further, a series of scenarios with different setups of sediment-related parameters were tested to explore the possibility of a 2-D model to simulate morphological changes at a natural bend, and to investigate how much physical complexity is needed for reliable modeling. The results suggest that a 2-D depth-averaged model can reconstruct the hydrodynamic and morphological features at a bend reasonably provided that the model addresses a secondary flow correction, and reasonably parameterize grain-sizes within a channel in a pragmatic way. The factors, such as sediment transport formula and roughness height, have relatively less significance on the bed change pattern at a bend. The study reveals that the secondary flow effect and grain-size parameterization should be given a first priority among other parameters when modeling bed deformation at a natural bend using a 2-D model.
- Social Sciences
- Geography and Environment
Published inWater Resources Research
Pages6348 - 6364
CitationGUAN, M. ... et al, 2016. Physical complexity to model morphological changes at a natural channel bend. Water Resources Research, 52 (8), pp. 6348-6364.
Publisher© American Geophysical Union
- VoR (Version of Record)
Publisher statementThis work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
NotesAn edited version of this paper was published by AGU. Copyright 2016 American Geophysical Union. The final published version can be found here http://dx.doi.org/10.1002/2015WR017917