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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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de Vet, P.L.M. (author), van Prooijen, Bram (author), Schrijvershof, R. A. (author), van der Werf, J. J. (author), Ysebaert, T. (author), Schrijver, M. C. (author), Wang, Zhengbing (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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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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Flores, Raúl P. (author), Rijnsburger, S. (author), Meirelles, Saulo (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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Kumar, M. (author)
doctoral thesis 2018
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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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Chavarrias Borras, V. (author), Schielen, R.M.J. (author), Ottevanger, Willem (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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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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Meirelles, Saulo (author)
This thesis examines the effects of the stratified tidal flow on the morphodynamics of the Dutch inner shelf. The south portion of the Dutch inner shelf is strongly influenced by the Rhine River ROFI (Region Of Freshwater Influence), which is generated by the discharge from the Rhine River through the Rotterdam waterways. Under stratified...
doctoral thesis 2019
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Henriquez, M. (author)
This thesis is about the hydrodynamic processes that occur when a nearshore sandbar migrates towards the shore driven by the waves. These processes are relevant because process-based morphological models have difficulty simulating coastal accretion events in contrast to erosion events. Simulating accretion events is important for engineering...
doctoral thesis 2019
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Osório, A.L.N.A. (author), Mosselman, E. (author), Franca, M.J. (author), Creech, C. (author)
Longitudinal training walls are man-made river dividers. They were built in the Netherlands as a replacement of perpendicular groynes as a river training alternative to decrease flood risk and stop the ongoing bed degradation, while still allowing safe navigation. The efficiency of these structures relies on the long-term stability of the two...
conference paper 2020
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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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Zhou, Z. (author)
Estuaries are partially enclosed water bodies where river water mixes with sea water. Estuaries provide important ecological functions which are strongly regulated by estuarine hydrodynamics and sediment dynamics, and also by human interventions. Sustainable management of such systems therefore requires a thorough understanding of the interplay...
doctoral thesis 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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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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Helmons, R.L.J. (author), de Wit, Lynyrd (author), de Stigter, Henko (author), Spearman, Jeremy (author)
Over the past decade, deep-sea mining (DSM) has received renewed interest due to scarcity of raw materials. Deep-sea mining has been spurred by the need for critical resources to support growing populations, urbanization, high-tech applications and the development of a green energy economy. Nevertheless, an improved understanding of how mining...
review 2022
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Tas, S.A.J. (author)
Over the last decades, mangrove forests have suffered immense and rapid losses worldwide. In recognition of their important socio-economic and environmental functions, many attempts have been made to both protect the remaining mangrove coastlines and restore eroding sites. Unfortunately, many rehabilitation attempts have failed, lacking a...
doctoral thesis 2022
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