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Role of turbulent kinetic energy modulation by particle–fluid interaction in sediment pick-up

Keetels, G.H. (author), Chauchat, Julien (author), Breugem, W.P. (author)

Reliable prediction of the erosion rate of sediment beds is important for many applications in coastal and river engineering. Theoretical understanding of empirically derived scaling relations is still lacking. This applies in particular for the scaling anomaly between low and high Shields number conditions. In this work, the erosion process is...

journal article 2023

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Modeling Multi-Fraction Coastal Aeolian Sediment Transport With Horizontal and Vertical Grain-Size Variability

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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Depth-Resolved Modelling of Intra-Swash Morphodynamics Induced by Solitary Waves

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^® 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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Novel sediment sampling method provides new insights into vertical grain size variability due to marine and aeolian beach processes

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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Turbidity maxima in estuarine networks: Dependence on fluvial sediment input and local deepening/narrowing with an exploratory model

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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Chenier Formation Through Wave Winnowing and Tides

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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Sediment transport prediction in sewer pipes during flushing operation

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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Study of Sediment Transport in a Tidal Channel-Shoal System: Lateral Effects and Slack-Water Dynamics

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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Modeling the Transition to High Sediment Concentrations as a Response to Channel Deepening in the Ems River Estuary

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 ³ ) to high (>10...

journal article 2019

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Ill posedness in modelling two-dimensional morphodynamic problems: Effects of bed slope and secondary flow

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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Observations of Bedform Migration and Bedload Sediment Transport in Combined Wave-Current Flows

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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Wave Generation of Gravity-Driven Sediment Flows on a Predominantly Sandy Seabed

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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Sediment Transport of Fine Sand to Fine Gravel on Transverse Bed Slopes in Rotating Annular Flume Experiments

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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The Importance of Combined Tidal and Meteorological Forces for the Flow and Sediment Transport on Intertidal Shoals

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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Three-Dimensional Sediment Dynamics in Well-Mixed Estuaries: Importance of the Internally Generated Overtide, Spatial Settling Lag, and Gravitational Circulation

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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The impact of storms and stratification on sediment transport in the Rhine region of freshwater influence

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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Development and Extension of An Aggregated Scale Model: Part 1 – Background to ASMITA

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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Mathematical analysis of the Saint-Venant-Hirano model for mixed-sediment morphodynamics

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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Seasonal variability in M2 and M4 tidal constituents and its implications for the coastal residual sediment transport

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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Detailed simulation of morphodynamics: 3. Ripples and dunes

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