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Chavarrias Borras, V. (author), Schielen, Ralph M.J. (author), Ottevanger, W. (author), Blom, A. (author)
A two-dimensional model describing river morphodynamic processes under mixed-size sediment conditions is analysed with respect to its well posedness. Well posedness guarantees the existence of a unique solution continuously depending on the problem data. When a model becomes ill posed, infinitesimal perturbations to a solution grow infinitely...
journal article 2019
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Dijkstra, Y.M. (author), Schuttelaars, H.M. (author), Schramkowski, G.P. (author), Brouwer, R.L. (author)
Many estuaries are strongly modified by human interventions, including substantive channel deepening. In the Ems River Estuary (Germany and Netherlands), channel deepening between the 1960s and early 2000s coincided with an increase in the maximum near-bed suspended sediment concentration from moderate (∼1 kg/m <sup>3</sup> ) to high (&gt;10...
journal article 2019
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Wengrove, M. E. (author), Foster, D. L. (author), Lippmann, T. C. (author), de Schipper, M.A. (author), Calantoni, J. (author)
Bedload transport is an important mechanism for sediment flux in the nearshore. Yet few studies examine the relationship between bedform evolution and net sediment transport. Our work contributes concurrent observations of bedform mobility and bedload transport in response to wave dominant, current dominant, and combined wave-current flows in...
journal article 2019
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Flores, Raúl P. (author), Rijnsburger, S. (author), Meirelles Nunes da Rocha, S. (author), Horner-Devine, Alexander R. (author), Souza, Alejandro J. (author), Pietrzak, J.D. (author), Henriquez, M. (author), Reniers, A.J.H.M. (author)
Wave-supported gravity flows (WSGFs) generate rates of sediment flux far exceeding other cross-shelf transport processes, contributing disproportionately to shelf morphology and net cross-shelf fluxes of sediment in many regions worldwide. However, the conditions deemed necessary for the formation of WSGF limit them to a narrow set of shelf...
journal article 2018
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Wei, X. (author), Kumar, M. (author), Schuttelaars, H.M. (author)
To investigate the dominant sediment transport and trapping mechanisms, a semi-analytical three-dimensional model is developed resolving the dynamic effects of salt intrusion on sediment in well-mixed estuaries in morphodynamic equilibrium. As a study case, a schematized estuary with a converging width and a channel-shoal structure...
journal article 2018
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de Vet, P.L.M. (author), van Prooijen, B.C. (author), Schrijvershof, R. A. (author), van der Werf, J. J. (author), Ysebaert, T. (author), Schrijver, M. C. (author), Wang, Z.B. (author)
Estuarine intertidal areas are shaped by combined astronomical and meteorological forces. This paper reveals the relative importance of tide, surge, wind, and waves for the flow and sediment transport on large intertidal shoals. Results of an intensive field campaign have been used to validate a numerical model of the Roggenplaat intertidal...
journal article 2018
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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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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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Townend, I (author), Wang, Z.B. (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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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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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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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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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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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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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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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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Stive, M.J.F. (author), De Vriend, H.J. (author)
journal article 1995
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