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Samir-Saleh, M. (author), Crosato, A. (author)
Flume experiments and field observations demonstrating the effects of vegetation on river planforms are reported in literature, but numerical studies of these effects at the river scale are lacking. We investigated the effects of vegetation in a 2D morphodynamic model using submodels for flow resistance and colonisation of newly formed deposits....
conference paper 2010
document
Nabi, M. (author)
Alluvial open channel beds often exhibit statistically periodic irregularities, known as dunes. Dunes have considerable effects on sediment transport and flow resistance. When growing during a flood, the dunes create more resistance and flood levels may rise significantly. Accurate prediction of dune properties therefore contributes to effective...
doctoral thesis 2012
document
Nabi, M. (author), De Vriend, H.J. (author), Mosselman, E. (author), Sloff, C.J. (author), Shimizu, Y. (author)
The paper describes a numerical model for simulating sediment transport with eddy-resolving 3-D models. This sediment model consists of four submodels: pickup, transport over the bed, transport in the water column and deposition, all based on a turbulent flow model using large-eddy simulation. The sediment is considered as uniform rigid...
journal article 2013
document
Blom, A. (author)
This paper presents an assessment of the strengths and weaknesses of four sediment continuity models for nonuniform sediment by applying these models to an aggradational flume experiment that is dominated by nonuniform sediment and dunes. The author makes simulations of the flume experiment using four numerical morphodynamic model systems to...
journal article 2008
document
Crosato, A. (author)
Meander migration models include an as yet poorly investigated source of numerical errors related to the computation of the channel curvature, which are amplified by the procedure of adding and deleting grid points as the river planform evolves. The methods adopted to reduce these errors may influence size, form, and migration rate of the...
journal article 2007
document
Nabi, M. (author), De Vriend, H.J. (author), Mosselman, E. (author), Sloff, C.J. (author), Shimizu, Y. (author)
We present a 3-D physics-based high-resolution modeling approach to the dynamics of underwater ripples and dunes. The flow is modeled by large eddy simulation on a Cartesian grid with local refinements. The sediment transport is modeled by computing pickup, transport over the bed, transport in the water column, and deposition of rigid spherical...
journal article 2013
document
Nabi, M. (author), De Vriend, H.J. (author), Mosselman, E. (author), Sloff, C.J. (author), Shimizu, Y. (author)
We present a three-dimensional high-resolution hydrodynamic model for unsteady incompressible flow over an evolving bed topography. This is achieved by using a multilevel Cartesian grid technique that allows the grid to be refined in high-gradient regions and in the vicinity of the river bed. The grid can be locally refined and adapted to the...
journal article 2012
document
Vargas-Luna, Andrés (author), Duro, G. (author), Crosato, A. (author), Uijttewaal, W.S.J. (author)
While the scientific community has long recognized that alluvial rivers are the product of interactions between flowing water and bed material transport, it is increasingly evident that vegetation mediates these interactions and influences the stream channel characteristics. In a novel set of mobile bed laboratory experiments with variable...
journal article 2019
document
Arkesteijn, E.C.M.M. (author), Blom, A. (author), Czapiga, M.J. (author), Chavarrias Borras, V. (author), Labeur, R.J. (author)
An engineered alluvial river (i.e., a fixed-width channel) has constrained planform but is free to adjust channel slope and bed surface texture. These features are subject to controls: the hydrograph, sediment flux, and downstream base level. If the controls are sustained (or change slowly relative to the timescale of channel response), the...
journal article 2019
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