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Tidal stream turbines are becoming an affordable option for harvesting sustainable energy in coastal areas. They can be retrofitted in barrages, providing an integral solution for flood protection and emission-free power generation, within environmental constraints. To optimize t ...
Coastal flood risk is expected to increase due to climate change and population
growth. Much of our coastlines is protected by “grey” infrastructure such as a dike.
Dike maintenance and strengthening requires ever increasing capital and space,
putting their economic v ...
The tidal flow between bridge pillars and through open barriers is a promising source of ocean energy which can be exploited using tidal stream turbines, as proven recently by operational demonstration plants. The aim of this study is to clarify the consequences for the power out ...
The ability to estimate the erosion rate along an underwater breach face is crucial to understand the evolution of breaching failure. To this end, breaching erosion models were developed and applied in numerical models. However, these erosion models have never been validated, owi ...
Recent analysis of equilibrium and quasi-equilibrium channel geometry in engineered (fixed-width) rivers has successfully shown that two temporal scales can be distinguished, with quasi-static (long-term) and dynamic (short-term) components. This distinction is based on the fact ...
Groynes have been replaced by longitudinal training walls in an 11-km long pilot project to optimize training of the river Waal in the Netherlands. These train­ ing walls improve navigability, reduce flood levels, create a sheltered second channel with more favourable ecological ...
Coastal infrastructure, such as bridges and storm surge barriers with weirs, provides an attractive location for harvesting renewable energy using tidal turbines. Often stone layers are applied downstream of coastal infrastructure to protect the sea bed from erosion. However, lit ...
Breaching flow slides are accompanied by the generation of turbidity currents. Measurements of these currents are critical for understanding the interaction between the turbidity current and the slope surface, as well as for the validation of numerical models. However, there are ...

The performance of a weir-mounted tidal turbine

Field observations and theoretical modelling

An economical way to harvest tidal energy is by integrating free stream turbines in coastal infrastructure. While numerous studies have investigated how turbines should be arranged in idealized geometries to optimize their performance, only a few have considered the influence of ...
This paper starts with surveying the state-of-the-art knowledge of breaching flow slides, with an emphasis on the relevant fluid mechanics. The governing physical processes of breaching flow slides are explained. The paper highlights the important roles of the associated turbidit ...
Breaching flow slides result in a turbidity current running over and directly interacting with the eroding, submarine slope surface, thereby promoting further sediment erosion. The investigation and understanding of this current are crucial, as it is the main parameter influencin ...
A particle-mesh strategy is presented for scalar transport problems which provides diffusion-free advection, conserves mass locally (i.e. cellwise) and exhibits optimal convergence on arbitrary polyhedral meshes. This is achieved by expressing the convective field naturally locat ...
By combining concepts from particle-in-cell (PIC) and hybridized discontinuous Galerkin (HDG) methods, we present a particle–mesh scheme for flow and transport problems which allows for diffusion-free advection while satisfying mass and momentum conservation – locally and globall ...
Coastal infrastructure, such as bridges and storm surge barriers with weirs, provides an attractive location for harvesting renewable energy using tidal turbines. Often stone layers are applied downstream of coastal infrastructure to protect the sea bed from erosion. However, lit ...
In 2015 heeft Tocardo met een consortium van bedrijven in een van de zuidelijke doorstroomopeningen van de Oosterschelde-stormvloedkering (Roompot 8) een getijdencentrale gerealiseerd, die in december van dat jaar in gebruik is genomen. Het project Oosterschelde Tidal Power (OTP) ...
Flow separation and its control have been the subject of intensive research for decades. Flow separation occurs when the boundary layer loses contact with the associated confining wall, which is usually caused by a pressure gradient acting against the local flow direction. Numero ...
An engineered alluvial river (i.e., a fixed-width channel) has constrained planform but is free to adjust channel slope and bed surface texture. These features are subject to controls: the hydrograph, sediment flux, and downstream base level. If the controls are sustained (or cha ...
Recent studies have revealed that breaching, rather than liquefaction, is the dominant failure process in underwater slopes of fine sand and the main driver of observed flow slides in nature. As a result, breaching is getting more attention from hydraulic and geotechnical researc ...

Scour at the eastern scheldt storm surge barrier

Linking laboratory experiments to field observations

The Eastern Scheldt storm surge barrier is one of the primary flood defense structures in the Netherlands. Since its construction, large scour holes have developed downstream of the applied bed protection at both sides of the inlet that have grown much deeper than foreseen during ...