Rights statement: An edited version of this paper was published by AGU. Copyright 2016 American Geophysical Union.
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Rights statement: An edited version of this paper was published by AGU. Copyright 2016 American Geophysical Union.
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Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Physical complexity to model morphological changes at a natural channel bend
AU - Guan, M.
AU - Wright, N.G.
AU - Sleigh, P.A.
AU - Ahilan, S.
AU - Lamb, R.
N1 - An edited version of this paper was published by AGU. Copyright 2016 American Geophysical Union.
PY - 2016/8
Y1 - 2016/8
N2 - This study developed a two-dimensional (2D) 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 were 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 2D model to simulate morphological changes at a natural bend, and to investigate how much physical complexity is needed for reliable modelling. The results suggest that a 2D 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 parameterise 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 parameterisation should be given a first priority among other parameters when modelling bed deformation at a natural bend using a 2D model.
AB - This study developed a two-dimensional (2D) 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 were 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 2D model to simulate morphological changes at a natural bend, and to investigate how much physical complexity is needed for reliable modelling. The results suggest that a 2D 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 parameterise 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 parameterisation should be given a first priority among other parameters when modelling bed deformation at a natural bend using a 2D model.
U2 - 10.1002/2015WR017917
DO - 10.1002/2015WR017917
M3 - Journal article
VL - 52
SP - 6348
EP - 6364
JO - Water Resources Research
JF - Water Resources Research
SN - 0043-1397
IS - 8
ER -