Numerical Simulation of Flow and Suspended Sediment Transport in the Distributary Channel Networks

Flow and suspended sediment transport in distributary channel networks play an important role in the evolution of deltas and estuaries, as well as the coastal environment. In this study, a 1D flow and suspended sediment transport model is presented to simulate the hydrodynamics and suspended sediment transport in the distributary channel networks. The governing equations for river flow are the Saint-Venant equations and for suspended sediment transport are the nonequilibrium transport equations. The procedure of solving the governing equations is firstly to get the matrix form of the water level and suspended sediment concentration at all connected junctions by utilizing the transformation of the governing equations of the single channel. Secondly, the water level and suspended sediment concentration at all junctions can be obtained by solving these irregular spare matrix equations. Finally, the water level, discharge, and suspended sediment concentration at each river section can be calculated. The presented 1D flow and suspended sediment transport model has been applied to the Pearl River networks and can reproduce water levels, discharges, and suspended sediment concentration with good accuracy, indicating this that model can be used to simulate the hydrodynamics and suspended sediment concentration in the distributary channel networks.

[1]  P. Ashmore.  Laboratory modelling of gravel braided stream morphology , 2007 .

[2]  H. Fang,et al.  One-dimensional numerical simulation of non-uniform sediment transport under unsteady flows , 2008 .

[3]  F. M. Holly,et al.  New numerical/physical framework for mobile-bed modelling , 1990 .

[4]  Frank Liu,et al.  Applying microprocessor analysis methods to river network modelling , 2014, Environ. Model. Softw..

[5]  F. Holly,et al.  Modeling of Riverbed Evolution for Bedload Sediment Mixtures , 1989 .

[6]  Howard H. Chang.  Modeling of River Channel Changes , 1984 .

[7]  Dirk Schwanenberg,et al.  Coupled 1D–3D hydrodynamic modelling, with application to the Pearl River Delta , 2009 .

[8]  Ben Chie Yen,et al.  Diffusion-Wave Flood Routing in Channel Networks , 1981 .

[9]  P. Ashmore.  How do gravel-bed rivers braid? , 1991 .

[10]  Weiming Wu,et al.  One-dimensional numerical model for nonuniform sediment transport under unsteady flows in channel networks , 2004 .

[11]  L. Rijn.  Sediment Transport, Part II: Suspended Load Transport , 1984 .

[12]  Rudy Slingerland,et al.  Routing of Heterogeneous Sediments over Movable Bed: Model Development , 1992 .

[13]  A. Papanicolaou,et al.  One-dimensional hydrodynamic/sediment transport model applicable to steep mountain streams , 2004 .

[14]  Julian Icarus Allen,et al.  Quantifying uncertainty in high-resolution coupled hydrodynamic-ecosystem models , 2007 .

[15]  R. Runkel,et al.  One-Dimensional Transport with Inflow and Storage (OTIS): A Solute Transport Model for Small Streams , 1991 .

[16]  A 2-D Hydrodynamic Model for the River, Lake and Network System in the Jingjiang Reach on the Unstructured Quadrangles , 2010 .