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Schramkowski, G.P. (author), De Swart, H.E. (author), Schuttelaars, H.M. (author)
A three-dimensional numerical model with a prognostic salinity field is used to investigate the effect of a partial slip bottom boundary condition on lateral flow and sediment distribution in a transect of a tidally dominated channel. The transect has a symmetrical Gaussian cross-channel bottom profile. For a deep, well-mixed, tidally dominated...
journal article 2009
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Stecca, G. (author), Siviglia, A. (author), Blom, A. (author)
Sediment of different size are transported in rivers under the action of flow. The first and still most popular sediment continuity model able to deal with mixed sediment is the so-called active layer model proposed by Hirano (1971, 1972). In this paper, we consider the one-dimensional hydromorphodynamic model given by the Saint-Venant equations...
journal article 2014
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Gräwe, U. (author), Burchard, H. (author), Müller, M. (author), Schuttelaars, H.M. (author)
We use an observational data set of tidal gauges in the North Sea to investigate the annual cycle of the M2 and M4 amplitudes and phases. The sea surface elevation amplitude of the M2 can vary by 8–10% and the M4 amplitude by 12–30% over the course of the year, with larger amplitudes in summer. The annual phase variations are in the range of 3...
journal article 2014
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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
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Klein, M.D. (author), Schuttelaars, H.M. (author)
The initial growth of bed perturbations on planar sloping beaches under the forcing of obliquely incident, breaking waves is investigated using a state?of?the?art numerical model. This allows for a systematic investigation of the sensitivity of the spatial structures of the bed perturbations and their growth and migration rates to different...
journal article 2005
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Ter Brake, M.C. (author), Schuttelaars, H.M. (author)
In many tidal embayments, bottom patterns, such as the channel-shoal systems of the Wadden Sea, are observed. To gain understanding of the mechanisms that result in these bottom patterns, an idealized model is developed and analyzed for short tidal embayments. In this model, the water motion is described by the depth- and width-averaged shallow...
journal article 2009
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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
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Stive, M.J.F. (author), De Vriend, H.J. (author)
journal article 1995
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Li, W. (author), De Vriend, H.J. (author), Wang, Z. (author), Van Maren, D.S. (author)
High-resolution morphological modeling of fluvial processes with complex, rapidly varying flows has been limited so far by model accuracy or computational efficiency. One of the most widely used numerical algorithms is based on the total variation diminishing method, solved by either upwind or centered approaches. An upwind scheme preserves high...
journal article 2013
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Lam, N.T. (author), Verhagen, H.J. (author), Van der Wegen, M. (author)
Hydraulic characteristics of flow in a tidal inlet act an important role in morphological changes of the inlet. In normal conditions, inlet currents flush sediment out of the inlet to maintain its opening against longshore sediment transports that tend to close the inlet. The currents in the inlet are contributed by the tides and also from...
journal article 2004
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Montes, Carlos (author), Ortiz, Hachly (author), Vanegas, Sergio (author), Kapelan, Z. (author), Berardi, Luigi (author), Saldarriaga, Juan (author)
This paper presents a novel model for predicting the sediment transport rate during flushing operation in sewers. The model was developed using the Evolutionary Polynomial Regression Multi-Objective Genetic Algorithm (EPR-MOGA) methodology applied to new experimental data collected. Using the new model, a series of design charts were...
journal article 2021
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Zhou, Z. (author), Ge, Jianzhong (author), van Maren, D.S. (author), Wang, Zhengbing (author), Kuai, Y. (author), Ding, Pingxing (author)
Lateral flows redistribute sediment and influence the morphodynamics of channel-shoal systems. However, our understanding of lateral transport of suspended sediment during high and low water slack is still fairly limited, especially in engineered estuaries. Human interventions such as dike-groyne structures influence lateral exchange...
journal article 2021
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Kranenborg, Joost W.M. (author), Campmans, Geert H.P. (author), Jacobsen, Niels G. (author), van der Werf, Jebbe J. (author), Reniers, A.J.H.M. (author), Hulscher, Suzanne J.M.H. (author)
We present a fully coupled 2DV morphodynamic model, implemented in OpenFOAM<sup>®</sup> that is capable of simulating swash-zone morphodynamics of sandy beaches. The hydrodynamics are described by the Reynolds-averaged Navier–Stokes (RANS) equations with a (Formula presented.) turbulence model and the Volume of Fluid (VoF) approach for...
journal article 2022
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van IJzendoorn, Christa (author), Hallin, E.C. (author), Cohn, Nicholas (author), Reniers, A.J.H.M. (author), de Vries, S. (author)
In sandy beach systems, the aeolian sediment transport can be governed by the vertical structure of the sediment layers at the bed surface. Here, data collected with a newly developed sand scraper is presented to determine high-resolution vertical grain size variability and how it is affected by marine and aeolian processes. Sediment samples...
journal article 2022
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Wang, Jinyang (author), Dijkstra, Y.M. (author), de Swart, Huib E. (author)
An estuarine turbidity maximum (ETM) results from various subtidal sediment transport mechanisms related to, e.g., river, tides, and density gradients, which have been extensively analysed in single-channel estuaries. However, ETMs have also been found in estuaries composed of multiple interconnected tidal channels, where the water and...
journal article 2022
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van IJzendoorn, Christa (author), Hallin, E.C. (author), Reniers, A.J.H.M. (author), de Vries, S. (author)
Grain size affects the rates of aeolian sediment transport on beaches. Sediment in coastal environments typically consists of multiple grain-size fractions and exhibits spatiotemporal variations. Still, conceptual and numerical aeolian transport models are simplified and often only include a single fraction that is constant over the model...
journal article 2023
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Townend, I (author), Wang, Zhengbing (author), Stive, M.J.F. (author), Zhou, Z. (author)
Whilst much attention has been given to models that describe wave, tide and sediment transport processes in sufficient detail to determine the local changes in bed level over a relatively detailed representation of the bathymetry, far less attention has been given to models that consider the problem at a much larger scale (e.g. that of...
journal article 2016
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Flores, Raúl P. (author), Rijnsburger, S. (author), Horner-Devine, Alexander R. (author), Souza, Alejandro J. (author), Pietrzak, J.D. (author)
We present measurements of along and across-shore sediment transport in a region of the Dutch coast 10 km north of the Rhine River mouth. This section of the coast is characterized by strong vertical density stratification because it is within the midfield region of the Rhine region of freshwater influence, where processes typical of the far...
journal article 2017
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Baar, A.W. (author), de Smit, Jaco (author), Uijttewaal, W.S.J. (author), Kleinhans, Maarten G. (author)
Large-scale morphology, in particular meander bend depth, bar dimensions, and bifurcation dynamics, are greatly affected by the deflection of sediment transport on transverse bed slopes due to gravity and by secondary flows. Overestimating the transverse bed slope effect in morphodynamic models leads to flattening of the morphology, while...
journal article 2018
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Tas, S.A.J. (author), van Maren, D.S. (author), Reniers, A.J.H.M. (author)
Cheniers are ridges consisting of coarse-grained sediments, resting on top of the fine sediment that forms the otherwise muddy coast. In this paper, we use Delft3D to explore how cheniers are formed through wave winnowing. We identify three phases of chenier development: (a) a winnowing phase, during which mud is washed out of the seabed...
journal article 2022
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