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Reniers, A. (author)
This progress report refers to part the work done within the framework of the Dutch Center for Coastal Research (NCK). The primary objective of our research is to develop knowledge and methods for the prediction of the hydrodynamic conditions for the Dutch coast taking into account the morphodynamic behaviour in the nearshore zone. In general...
report 1990
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Reniers, A. (author), Van Dongeren, A. (author)
In the following we consider the forcing of long waves by normally or obliquely incident grouped short waves, also known as surf beat. Two mechanisms responsible for the generation of long waves are considered: the release of the bound long waves associated with changes in the spatial variation of the incident short wave energy [Longuet-Higgins...
report 1990
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Reniers, A.J.H.M. (author)
doctoral thesis 1999
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Van Dongeren, A. (author), Reniers, A. (author)
In this paper the nonlinear numerical model SHORECIRC is applied to simulate the intragravity wave conditions on two days during the 1990 Delilah campaign. In order to simulate the wave conditions an algorithm has been derived which synthesizes a directional of/shore wavefield from data including the bound, directional low-frequency components....
report 1999
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Stive, M.J.F. (author), Terrile, E. (author), Reniers, A.J.H.M. (author), Verhagen, H.J. (author)
Threshold of motion of coarse particles under regular shoaling waves is studied. Experiments were performed to investigate the effects of bed fluid acceleration on coarse particle stability. By varying wave height, wave period and water depth combinations of similar peak orbital velocities and weak to strong intra-wave accelerations were created...
conference paper 2005
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Stive, M.J.F. (author), Reniers, A.J.H.M. (author), Terrile, E. (author), Verhagen, H.J. (author)
The threshold of motion of coarse particles under regular shoaling waves is studied. Experiments are performed to investigate the effects of bed fluid acceleration on coarse particle stability. By varying wave height, wave period and water depth, combinations of similar peak orbital velocities and weak to strong intra-wave accelerations were...
conference paper 2005
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Terrile, E. (author), Reniers, A.J.H.M. (author), Stive, M.J.F. (author), Tromp, M. (author), Verhagen, H.J. (author)
Incipient motion of coarse particles under regular shoaling waves is examined. Experiments are performed to investigate the effects of bed fluid acceleration on coarse particle stability. By varying wave height, wave period and water depth, combinations of similar peak orbital velocities and weak to strong intra-wave accelerations were created....
journal article 2005
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Van Dongeren, A. (author), Battjes, J.A. (author), Janssen, T. (author), Van Noorloos, J. (author), Steenhauer, K. (author), Steenbergen, G. (author), Reniers, A. (author)
The growth rate, shoreline reflection, and dissipation of low?frequency waves are investigated using data obtained from physical experiments in the Delft University of Technology research flume and by parameter variation using the numerical model Delft3D?SurfBeat. The growth rate of the shoaling incoming long wave varies with depth with an...
journal article 2007
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Reniers, A.J.H.M. (author), MacMahan, J.H. (author), Thornton, E.B. (author), Stanton, T.P. (author)
Numerical computations are used to explain the presence of very low frequency motions (VLFs), with frequencies less than 0.004 Hz, in the rip current velocity signals observed during the Rip-current field Experiment (RIPEX) field experiment. Observations show that the VLF motions are most intense within the surfzone and then quickly taper off in...
journal article 2007
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Ruessink, B.G. (author), Kuriyama, Y. (author), Reniers, A.J.H.M. (author), Roelvink, J.A. (author), Walstra, D.J.R. (author)
We compare predictions of a coupled, wave-averaged, cross-shore waves-currents-bathymetric evolution model to observations of onshore and offshore nearshore sandbar migration. The observations span a 10- and 44-day period with onshore/offshore bar migration at Duck, North Carolina, and at Hasaki, Kashima Coast, Japan, respectively, a 3.5-month...
journal article 2007
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Reniers, M.G.C.E. (author)
doctoral thesis 2007
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Den Heijer, C. (author), Reniers, A.J.H.M. (author), Van de Graaff, J. (author), Van Gelder, P.H.A.J.M. (author)
Coastal dunes protect low lying coastal areas against the sea. Extreme waves and water levels during severe storms may cause breaching of the dunes. Consequently, serious damage due to flooding and direct wave attack could occur, resulting in loss of life and property. Proper coastal management implies that reinforcement measures will be taken...
conference paper 2008
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Henriquez, M. (author), Reniers, A.J.H.M. (author), Ruessink, B.G. (author), Stive, M.J.F. (author), Stanton, T.P. (author), Foster, D.L. (author)
Scale relations are necessary to choose proper sediment for physical models. The use of lightweight artificial sediment makes it possible to preserve the Reynolds number, Shields number and relative settling velocity altogether. There is also the possibility to preserve the Shields number in combination with the Dean number which would be more...
conference paper 2009
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De Schipper, M.A. (author), De Vries, S. (author), Henriquez, M. (author), Reniers, A.J.H.M. (author), De Koning Gans, H.J. (author), Labeur, R.J. (author), Stive, M.J.F. (author)
In this paper a new wave pool concept is presented using ship hulls as wave generators. To evaluate the potential of such a concept a towing tank experiment is conducted to investigate ship wave generation in a confined space. In the towing tank experiment various hull sizes and velocities are examined to maximize the generated wave height. The...
conference paper 2009
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Reniers, A.J.H.M. (author), MacMahan, J.H. (author), Thornton, E.B. (author), Stanton, T.P. (author), Henriquez, M. (author), Brown, J.W. (author), Brown, J.A. (author), Gallagher, E. (author)
The retention of floating matter within the surf zone on a rip-channeled beach is examined with a combination of detailed field observations obtained during the Rip Current Experiment and a three-dimensional (3-D) wave and flow model. The acoustic Doppler current profiler–observed hourly vertical cross-shore velocity structure variability over a...
journal article 2009
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Brown, J. (author), MacMahan, J. (author), Reniers, A.J.H.M. (author), Thornton, E. (author)
Absolute and relative diffusivity are measured on a rip-channeled beach using 30 position-tracking drifters released in clusters (4–12 drifters) deployed on 7 days with different wave forcing and tidal elevations at Sand City, Monterey Bay, California. Diffusivity and dispersion were found to be larger on days with rip current flow patterns and...
journal article 2009
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Reniers, A.J.H.M. (author), MacMahan, J.H. (author), Beron-Vera, F.J. (author), Olascoaga, M.J. (author)
The trapping and ejection of surfzone floating material is examined by unveiling Lagrangian Coherent Structures (LCSs) hidden in the pulsating rip?current surface velocity field produced by a three?dimensional numerical model resolving wave?group induced Very Low Frequency motions (VLFs). LCSs explain the typically observed patchiness of flotsam...
journal article 2010
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MacMahan, J.H. (author), Reniers, A.J.H.M. (author), Thornton, E.B. (author)
Observations of velocity fluctuations with periods between about 4 and 30 min, thus longer than infragravity waves and referred to as very low frequency (VLF) surf zone motions, are described and compared with numerical simulations. The VLF motions discussed here exclude instabilities (generated by the wave-driven alongshore current velocity...
journal article 2010
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Smit, M. (author), Reniers, A. (author), Stive, M.J.F. (author)
Nearshore sandbars appear with various patterns which may change over time. From observations, these changes seem to be related to changes in hydrodynamic conditions, although observed length scales could not be related directly to occurring wave conditions. The current work investigated the role of both the concurrent and previous hydrodynamics...
conference paper 2010
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Henriquez, M. (author), Reniers, A. (author), Ruessink, G. (author), Stive, M.J.F. (author)
To study onshore bar migration and the accompanying intra-wave sediment transport a wave flume experiment was conducted. The wave flume had a rigid bottom with a single bar profile. The focus of the experiment was to measure the hydrodynamics in the wave bottom boundary layer. The results show that the skewness of bottom stress is not only...
conference paper 2010
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