Chenier Dynamics

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...

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

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...

How tides and waves enhance aeolian sediment transport at the sand motor mega-nourishment

Expanding knowledge concerning the close entanglement between subtidal and subaerial processes in coastal environments initiated the development of the open-source Windsurf modeling framework that enables us to simulate<br/>multi-fraction sediment transport due to subtidal and subaerial processes simultaneously. The Windsurf framework couples...

Beach growth driven by intertidal sandbar welding

Seasonal variability in wave conditions drive corresponding cycles of erosion and accretion along sandy beaches. Despite the fact that these oscillations are well documented at numerous sites throughout the world, the physical processes driving beach recovery remain poorly understood. Using field data from a low sloping, dissipative beach in the...

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

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...

Hydrodynamic Drivers of Sediment Transport Across a Fringing Reef

Coral reefs are highly valuable ecosystems, which are under an increasing number of environmental pressures. Sedimentation and sediment transport patterns are among key physical drivers of coral reefs, so it is important to improve our understanding of these poorly studied dynamics on reefs. To this purpose, flume experiments were performed on a...

Detailed simulation of morphodynamics: 3. Ripples and dunes

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...

Detailed simulation of morphodynamics: 2. Sediment pickup, transport, and deposition

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...

Computational modelling of small-scale river morphodynamics

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...

Effect of bottom stress formulation on modelled flow and turbidity maxima in cross-sections of tide-dominated estuaries

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...

Modeling equilibrium bed profiles of short tidal embayments: On the effect of the vertical distribution of suspended sediment and the influence of the boundary conditions

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...

Morphology of pits, channels and trenches - part II: Model verification of Delft3D with PUTMOR dataset

Transport van sediment over steilranden en overlaten