Floris de Wit

Delft University of Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Marion Tissier

Delft University of Technology

Ad Reniers

Delft University of Technology

Dirk P. Rijnsdorp

Delft University of Technology

Arnold van Rooijen

University of Western Australia

Marcel Zijlema

Delft University of Technology

Matthieu A. de Schipper

Delft University of Technology

Bruno Castelle

Environnements et Paléoenvironnements Océaniques et Continentaux

Julia Hopkins

Northeastern University

Meagan Wengrove

Oregon State University

Cooperative Institutions

Delft University of Technology

Deltares

University of Twente

University of Western Australia

Takenaka (Japan)

The University of Tokyo

IHE Delft Institute for Water Education

State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering

Université de Pau et des Pays de l'Adour

University of Rochester

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

The Relationship between Sea-Swell Bound Wave Height and Wave Shape

Journal of Marine Science and Engineering (2020)

Floris de Wit Marion Tissier Ad Reniers

The nonlinear wave shape, expressed by skewness and asymmetry, can be calculated from surface elevation or pressure time series using bispectral analysis. Here, it is shown that the same analysis technique can be used to calculate the bound superharmonic wave height. Using measured near-bed pressures from three different field experiments, it is demonstrated that there is a clear relationship between this bound wave height and the nonlinear wave shape, independent of the measurement time and location. This implies that knowledge on the spatially varying bound wave height can be used to improve wave shape-induced sediment transport predictions. Given the frequency-directional sea-swell wave spectrum, the bound wave height can be predicted using second order wave theory. This paper shows that in relatively deep water, where conditions are not too nonlinear, this theory can accurately predict the bispectrally estimated bound superharmonic wave height. However, in relatively shallow water, the mismatch between observed and predicted bound wave height increases significantly due to wave breaking, strong currents, and increased wave nonlinearity. These processes are often included in phase-averaged wind-wave models that predict the evolution of the frequency-directional spectrum over variable bathymetry through source terms in a wave action balance, including the transfer of energy to bound super harmonics. The possibility to calculate and compare with the observed bound super harmonic wave height opens the door to improved model predictions of the bound wave height, nonlinear wave shape and associated sediment transport in large-scale morphodynamic models at low additional computational cost.

Wave shoaling

Wave height

Swell

Significant wave height

Airy wave theory

Cross-polarized wave generation

Subharmonic function

10.3390/jmse8090643

Cite

Citations (8)

Characterizing Wave Shape Evolution on an Ebb-Tidal Shoal

Journal of Marine Science and Engineering (2019)

Floris de Wit Marion Tissier Ad Reniers

Field measurements of waves and currents were obtained at ten locations on an ebb-tidal shoal seaward of Ameland Inlet for a six-week period. These measurements were used to investigate the evolution of the near-bed velocity skewness and asymmetry, as these are important drivers for wave-induced sediment tranport. Wave shape parameters were compared to traditionally used parameterizations to quantify their performance in a dynamic area with waves and tidal currents coming in from different directions over a highly variable bathymetry. Spatially and temporally averaged, these parameterizations compared very well to observed wave shape. However, significant scatter was observed. The largest deviations from the parameterization were observed at the shallowest locations, where the contribution of wave-induced sediment transport was expected to be the largest. This paper shows that this scatter was caused by differences in wave-breaking, nonlinear energy transfer rate, and spatial gradients in tidal currents. Therefore, it is proposed to include the prior evolution of the wave before reaching a location in future parameterizations in numerical modeling instead of only using local parameters to predict wave shape.

Shoal

Wave height

Wave shoaling

10.3390/jmse7100367

Cite

Citations (21)

OBSERVATIONS AND NUMERICAL MODEL RESULTS OF MORPHODYNAMIC FEEDBACK OWING TO WAVE-CURRENT INTERACTION

Coastal Sediments (2019)

Julia Hopkins Matthieu A. de Schipper Meagan Wengrove Floris de Wit Bruno Castelle

Predicting the evolution of mound formations in the nearshore, both natural (e.g.bars) and man-made (e.g.nourishments) requires an understanding of mixed wave-current flow on sediment transport.MODEX (Morphological Diffusivity EXperiment) used a wave-current-sediment flume to capture detailed spatial and temporal observations of sand mound evolution in shallow water.Imposed flow included waves-alone, currents-alone, and combined wave-currents.MODEX provides a test bed for understanding the impact of currents on waves around submerged bedforms and the feedback with morphology.Here, a wave-resolving model SWASH is used to simulate flow patterns around the mound as it diffuses, showing the impact of wave-current interaction on both mound evolution and scouring observed around the mound.Further, simulations initialized with a diffused mound show the feedback between 3D bed deformation and wave-current flow structures.The results provide a framework for understanding and implementing intra-wave sediment transport in waveresolving models.Extensions of the results to field conditions with mixed wave-current energy will be explored.

Numerical models

10.1142/9789811204487_0049

Cite

Citations (2)

Including the effect of depth-uniform ambient currents on waves in a non-hydrostatic wave-flow model

arXiv (Cornell University) (2023)

Dirk P. Rijnsdorp Arnold van Rooijen Ad Reniers Marion Tissier Floris de Wit

Currents can affect the evolution of waves in nearshore regions through altering their wavenumber and amplitude. Including the effect of ambient currents (e.g., tidal and wind-driven) on waves in phase-resolving wave models is not straightforward as it requires appropriate boundary conditions in combination with a large domain size and long simulation duration. In this paper, we extended the non-hydrostatic wave-flow model SWASH with additional terms that account for the influence of a depth-uniform ambient current on the wave dynamics, in which the current field can be taken from an external source (e.g., from observations or a circulation model). We verified the model ability by comparing predictions to results from linear theory, laboratory experiments and a spectral wave model that accounts for wave interference effects. With this extension, the model was able to account for current-induced changes to the wave field (i.e., changes to the wave amplitude, length and direction) due to following and opposing currents, and two classical examples of sheared currents (a jet-like current and vortex ring). Furthermore, the model captured the wave dynamics in the presence of strong opposing currents. This includes reflections of relatively small amplitude waves at the theoretical blocking point, and transmission of breaking waves beyond the theoretical blocking point for larger wave amplitudes. The proposed model extension allows phase-resolving models to more accurately and efficiently simulate the wave dynamics in coastal regions with tidal and/or wind-driven flows.

Wavenumber

10.48550/arxiv.2301.01725

Cite

Citations (0)

FIELD STUDY ON INFLUENCE OF TIDAL CURRENTS ON INTRA-WAVE SEDIMENT TRANSPORT

Coastal Engineering Proceedings (2018)

Floris de Wit Marion Tissier Ad Reniers

Sediment transport by currents and waves determines the evolution of shoals and channels on the ebb-tidal delta. The channels are an important conduit for shipping and are often dredged to maintain access at considerable cost. A better understanding of the sediment transport processes within the channels is the basis for a more cost-effective maintenance strategy. In the vicinity of ebb-tidal inlets, waves from offshore encounter tidal currents. Depending on the tidal phase, incoming waves face strong positive or negative current gradients. Besides changes in wave height, period and direction, the current gradients also affect the nonlinear wave shape and corresponding velocity profile.

Shoal

Tidal current

10.9753/icce.v36.currents.30

Cite

Citations (0)

INFRAGRAVITY WAVES AT A TIDAL INLET

Coastal Engineering Proceedings (2023)

Ad Reniers Floris de Wit Marion Tissier Dirk P. Rijnsdorp

The generation and propagation of infragravity waves at sandy coasts has received significant attention (e.g. Herbers et al., 1994). This is in contrast with tidal inlets where both observations and modeling studies are scarce. Here we present novel observations and modeling of infragravity waves over an ebb-tidal delta located at Ameland, the Netherlands. The objective is to understand the evolution of the free and bound infragravity waves as they propagate from the deeper shelf onto an ebb-tidal shoal and into the ebbchannel, establish their pathways and examine the potential in sediment transport. The latter is important in view of the anticipated large-scale ebb-tidal delta nourishment at this location to protect the coast from future storm impacts.

Shoal

Infragravity wave

Beach morphodynamics

10.9753/icce.v37.waves.33

Cite

Citations (0)

Including the effect of depth-uniform ambient currents on waves in a non-hydrostatic wave-flow model

Coastal Engineering (2023)

Dirk P. Rijnsdorp Arnold van Rooijen Ad Reniers Marion Tissier Floris de Wit

Wavenumber

10.1016/j.coastaleng.2023.104420

Cite

Citations (1)

Wave Shape Evolution from a Phase-Averaged Spectral Model

Journal of Marine Science and Engineering (2024)

Floris de Wit Marion Tissier Ad Reniers

In spectral wave models, the nonlinear triad source term accounts for the transfer of energy to the bound higher harmonics. This paper presents an extension to commonly used spectral models that resolves the evolution of the bound wave energy by keeping track of the energy that has been bound by the triad interactions. This extension is referred to as the bound wave evolution (BWE) model. From this, the spatial evolution of the bound wave height is obtained, which serves as a proxy for the nonlinear wave shape. The accuracy of these bound wave heights, and thus wave shape predictions, is highly dependent on the accuracy of the triad source term. Therefore, in this study, the capability of the LTA and SPB triad formulations to capture the growth of the bound wave height is evaluated. For both of these formulations, it is found that slope dependent calibration parameters are required. Overall, despite being computationally more expensive, the SPB method proves to be significantly more accurate in predicting the bound wave evolution. In the shoaling zone, where the bound wave energy is dominated by triads, the BWE model is well capable of predicting the nonlinear wave’s shape. In the surf zone, however, where a combination of triads and wave breaking control the spectral evolution, the BWE model over-predicts the bound wave height. Nevertheless, this paper shows the promising capabilities of spectral models to predict the nonlinear wave shape.

Wave model

10.3390/jmse12060944

Cite

Citations (0)