caa a22 4500 605546908 CHVBK 20210128100943.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s10236-015-0816-z doi (NATIONALLICENCE)springer-10.1007/s10236-015-0816-z Mixed-sediment transport modelling in Scheldt estuary with a physics-based bottom friction law [Elektronische Daten] [Qilong Bi, Erik Toorman] In this study, the main object is to investigate the performance of a few new physics-based process models by implementation into a numerical model for the simulation of the flow and morphodynamics in the Western Scheldt estuary. In order to deal with the complexity within the research domain, and improve the prediction accuracy, a 2D depth-averaged model has been set up as realistic as possible, i.e. including two-way hydrodynamic-sediment transport coupling, mixed sand-mud sediment transport (bedload transport as well as suspended load in the water column) and a dynamic non-uniform bed composition. A newly developed bottom friction law, based on a generalised mixing-length (GML) theory, is implemented, with which the new bed shear stress closure is constructed as the superposition of the turbulent and the laminar contribution. It allows the simulation of all turbulence conditions (fully developed turbulence, from hydraulic rough to hydraulic smooth, transient and laminar), and the drying and wetting of intertidal flats can now be modelled without specifying an inundation threshold. The benefit is that intertidal morphodynamics can now be modelled with great detail for the first time. Erosion and deposition in these areas can now be estimated with much higher accuracy, as well as their contribution to the overall net fluxes. Furthermore, Krone's deposition law has been adapted to sand-mud mixtures, and the critical stresses for deposition are computed from suspension capacity theory, instead of being tuned. The model has been calibrated and results show considerable differences in sediment fluxes, compared to a traditional approach and the analysis also reveals that the concentration effects play a very important role. The new bottom friction law with concentration effects can considerably alter the total sediment flux in the estuary not only in terms of magnitude but also in terms of erosion and deposition patterns. Springer-Verlag Berlin Heidelberg, 2015 Sediment transport nationallicence Mixed sediment nationallicence Generalised mixing-length theory nationallicence Bottom friction nationallicence Near-bottom sediment transport nationallicence Residual sediment transport nationallicence Bi Qilong Hydraulics Laboratory, Department of Civil Engineering, KU Leuven, Kasteelpark Arenberg 40, Box 2448, 3001, Leuven, Belgium aut Toorman Erik Hydraulics Laboratory, Department of Civil Engineering, KU Leuven, Kasteelpark Arenberg 40, Box 2448, 3001, Leuven, Belgium aut Ocean Dynamics Springer Berlin Heidelberg 65/4(2015-04-01), 555-587 1616-7341 65:4<555 2015 65 10236 https://doi.org/10.1007/s10236-015-0816-z text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10236-015-0816-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bi Qilong Hydraulics Laboratory, Department of Civil Engineering, KU Leuven, Kasteelpark Arenberg 40, Box 2448, 3001, Leuven, Belgium aut NATIONALLICENCE 700 1- Toorman Erik Hydraulics Laboratory, Department of Civil Engineering, KU Leuven, Kasteelpark Arenberg 40, Box 2448, 3001, Leuven, Belgium aut NATIONALLICENCE 773 0- Ocean Dynamics Springer Berlin Heidelberg 65/4(2015-04-01), 555-587 1616-7341 65:4<555 2015 65 10236