Observation of irregular wave transformation in the surf zone over a gently sloping sandy beach on the French Atlantic coastline

Within the surf zone which is the region extending from the seaward boundary of wave breaking to the limit of wave uprush, breaking waves are the dominant hydrodynamics acting as the key role for sediment transport and beach profile change. Breaking waves exhibit various patterns, principally depending on the incident wave steepness and the beach slope. Based on the equations of conservation of mass, momentum and energy, a theoretical model for wave transformation in and outside the surf zone was obtained, which is used to calculate the wave shoaling, wave set-up and set down and wave height distributions in and outside the surf zone. The analysis and comparison were made about the breaking point location and the wave height variation caused by the wave breaking and the bottom friction, and about the wave breaking criterion under regular and irregular breaking waves. Flume experiments relating to the regular and irregular breaking wave height distribution across the surf zone were conducted to verify the theoretical model. The agreement is good between the theoretical and experimental results.

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IRREGULAR WAVE TRANSFORMATION AFFECTED BY OPPOSING CURRENTS

Coastal Engineering Proceedings ◽

10.9753/icce.v20.53 ◽

1986 ◽

Vol 1 (20) ◽

pp. 53

Author(s):

Shigeki Sakai ◽

Kouestu Hiyamizu ◽

Hiroshi Saeki

Keyword(s):

Wave Height ◽

Present Model ◽

Surf Zone ◽

Transformation Model ◽

Irregular Waves ◽

Wave Transformation ◽

Irregular Wave ◽

Sea Bed ◽

Dimensionless Unit ◽

Deep Water Wave

Transformation of irregular waves affected by opposing currents on a sloping sea bed was discussed, experimentally and theoretically. It was found that representative values of wave height, such as a significant wave height, are larger before breaking and the wave height decaying occurs more promptly in a surf zone as opposing currents become dominant, and that characteristics of a irregular wave transformation are determined by the dimensionless unit width discharge q* and the deep water wave steepness. This means that the effects of opposing currents on irregular wave transformation are qualitatively identical to that on the regular waves. A transformation model of irregular waves affected by opposing currents was presented. In the model, formulations for a regular wave transformation, in which the effects of opposing currents were taken into account, were applied to individual waves defined by zero-down" cross-method from irregular wave profiles. Comparisons between experimental results and the prediction by the model showed that the present model gives a good explanation for wave height distributions and the experimental finding that the surf zone is moved offshore by opposing currents.

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WAVE HEIGHT DISTRIBUTION AND WAVE GROUPING IN SURF ZONE

Coastal Engineering Proceedings ◽

10.9753/icce.v18.4 ◽

1982 ◽

Vol 1 (18) ◽

pp. 4 ◽

Cited By ~ 1

Author(s):

Hajime Mase ◽

Yuichi Iwagaki

Keyword(s):

Wave Height ◽

Surf Zone ◽

Irregular Waves ◽

Wave Transformation ◽

Height Distribution ◽

Frequency Distributions ◽

Irregular Wave ◽

Wave Height Distribution ◽

Wave Heights ◽

Deep Water Wave

The main purpose of this paper is to propose a model for prediction of the spatial distributions of representative wave heights and the frequency distributions of wave heights of irregular waves in shallow-water including the surf zone. In order to examine the validity of the model, some experiments of irregular wave transformation have been made. In addition, an attempt has been made to clarify the spatial distribution of wave grouping experimentally. Especially the present paper focuses finding the effects of the bottom slope and the deep-water wave steepness on the wave height distribution and wave grouping.

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The coastal refraction-diffraction wave propagation model

Vietnam Journal of Mechanics ◽

10.15625/0866-7136/10140 ◽

1995 ◽

Vol 17 (4) ◽

pp. 6-12

Author(s):

Nguyen Tien Dat ◽

Dinh Van Manh ◽

Nguyen Minh Son

Keyword(s):

Wave Propagation ◽

Field Data ◽

Surf Zone ◽

Propagation Model ◽

Wave Transformation ◽

Diffraction Effect ◽

Linear Wave ◽

Diffraction Wave ◽

Linear Wave Propagation ◽

Wave Propagation Model

A mathematical model on linear wave propagation toward shore is chosen and corresponding software is built. The wave transformation outside and inside the surf zone is considered including the diffraction effect. The model is tested by laboratory and field data and gave reasonables results.

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Numerical Simulation of Wave Propagation, Breaking, and Setup on Steep Fringing Reefs

Water ◽

10.3390/w10091147 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1147 ◽

Cited By ~ 8

Author(s):

Shanju Zhang ◽

Liangsheng Zhu ◽

Jianhua Li

Keyword(s):

Finite Difference ◽

Finite Volume ◽

Boussinesq Equations ◽

Transformation Process ◽

Wave Transformation ◽

Computational Accuracy ◽

Irregular Wave ◽

Eddy Viscosity Model ◽

Fringing Reefs ◽

Volume Method

The prediction of wave transformation and associated hydrodynamics is essential in the design and construction of reef top structures on fringing reefs. To simulate the transformation process with better accuracy and time efficiency, a shock-capturing numerical model based on the extended Boussinesq equations suitable for rapidly varying topography with respect to wave transformation, breaking and runup, is established. A hybrid finite volume–finite difference scheme is used to discretize conservation form of the extended Boussinesq equations. The finite-volume method with a HLL Riemann solver is applied to the flux terms, while finite-difference discretization is applied to the remaining terms. The fourth-order MUSCL (Monotone Upstream-centered Schemes for Conservation Laws) scheme is employed to create interface variables, with in which the van-Leer limiter is adopted to improve computational accuracy on complex topography. Taking advantage of van-Leer limiter, a nested model is used to take account of both computational run time and accuracy. A modified eddy viscosity model is applied to better accommodate wave breaking on steep reef slopes. The established model is validated with laboratory measurements of regular and irregular wave transformation and breaking on steep fringing reefs. Results show the model can provide satisfactory predictions of wave height, mean water level and the generation of higher harmonics.

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Irregular Wave Transformation Affected by Opposing Currents

Coastal Engineering 1986 ◽

10.1061/9780872626003.053 ◽

1987 ◽

Author(s):

Shigeki Sakai ◽

Kouetsu Hiyamizu ◽

Hiroshi Saeki

Keyword(s):

Wave Transformation ◽

Irregular Wave

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Extended Elliptic Mild Slope Equation Incorporating the Nonlinear Shoaling Effect

Polish Maritime Research ◽

10.1515/pomr-2016-0045 ◽

2016 ◽

Vol 23 (s1) ◽

pp. 44-51 ◽

Cited By ~ 2

Author(s):

Qian-lu Xiao ◽

Chun-hui Li ◽

Xiao-yan Fu ◽

Mei-ju Wang

Keyword(s):

Dispersion Relation ◽

Nonlinear Wave ◽

Surf Zone ◽

Wave Dispersion ◽

Structure Design ◽

Coastal Engineering ◽

Wave Transformation ◽

Flume Experiments ◽

Mild Slope Equation ◽

Wave Shoaling

Abstract The transformation during wave propagation is significantly important for the calculations of hydraulic and coastal engineering, as well as the sediment transport. The exact wave height deformation calculation on the coasts is essential to near-shore hydrodynamics research and the structure design of coastal engineering. According to the wave shoaling results gained from the elliptical cosine wave theory, the nonlinear wave dispersion relation is adopted to develop the expression of the corresponding nonlinear wave shoaling coefficient. Based on the extended elliptic mild slope equation, an efficient wave numerical model is presented in this paper for predicting wave deformation across the complex topography and the surf zone, incorporating the nonlinear wave dispersion relation, the nonlinear wave shoaling coefficient and other energy dissipation factors. Especially, the phenomenon of wave recovery and second breaking could be shown by the present model. The classical Berkhoff single elliptic topography wave tests, the sinusoidal varying topography experiment, and complex composite slopes wave flume experiments are applied to verify the accuracy of the calculation of wave heights. Compared with experimental data, good agreements are found upon single elliptical topography and one-dimensional beach profiles, including uniform slope and step-type profiles. The results indicate that the newly-developed nonlinear wave shoaling coefficient improves the calculated accuracy of wave transformation in the surf zone efficiently, and the wave breaking is the key factor affecting the wave characteristics and need to be considered in the nearshore wave simulations.

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Assessment of surf zone zooplankton dynamics in a Southwestern Atlantic sandy beach: Seasonal cycle and tidal height influence

Estuarine Coastal and Shelf Science ◽

10.1016/j.ecss.2019.106307 ◽

2019 ◽

Vol 227 ◽

pp. 106307 ◽

Cited By ~ 1

Author(s):

M. Clara Menéndez ◽

Carla A. Baleani ◽

Martín R. Amodeo ◽

E. Marcelo Acha ◽

M. Cintia Piccolo

Keyword(s):

Seasonal Cycle ◽

Sandy Beach ◽

Surf Zone ◽

Tidal Height ◽

Southwestern Atlantic ◽

Zooplankton Dynamics

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Studi Hindcasting Dalam Menentukan Karakteristik Gelombang dan Klasifikasi Zona Surf Di Pantai Uluwatu, Bali

Journal of Marine and Aquatic Sciences ◽

10.24843/jmas.2019.v05.i01.p15 ◽

2018 ◽

Vol 5 (1) ◽

pp. 119

Author(s):

Karina Santoso ◽

I Dewa Nyoman Nurweda Putra ◽

I Gusti Bagus Sila Dharma

Keyword(s):

Wave Height ◽

Calculation Result ◽

Significant Wave Height ◽

Surf Zone ◽

Wind Data ◽

Wave Transformation ◽

Breaking Wave ◽

Significant Wave ◽

The World

Bali is one of the islands where there are many surf zones with various characteristics. In addition, Bali is also a heaven with a classy wave for the surfers of the world. One of the most challenging places to surf in Bali is Uluwatu Beach. Uluwatu Beach is ranked the 3rd best surf spot in the world version of CNN Travel in 2012. Wind causes sea waves, therefore wind data can be used to estimate the height and direction of the waves. Wave Hindcasting with Sverdrup, Munk and Bretschneider (SMB) method is calculated based on wind data for 10 years (2001 - 2010) from BMKG Ngurah Rai Station - Denpasar to obtain a significant wave height and period. In this research, it is necessary to approach through Hindcasting procedure, wave transformation analysis and surfing Terminology in determining the type of breaking wave and classification of surf zone in Uluwatu Beach area. Wave calculation result in Uluwatu Beach dominated by wave that coming from west side with significant wave height (Hs) of 0.98 m and significant wave period (Ts) of 5.21 s. The wave height due to the influence of wave refraction and shoaling is 0.976 m. The breaking wave height obtained from the calculation is 1.04 m at a depth of 0.849 m. From the result in this research, it can be concluded that the breaking wave type that occurred at Uluwatu Beach is plunging type according to the calculation result from its Irribaren number (0.4 <Ni <2.3). The classification of the surf zone at Uluwatu Beach based on its breakup type of wave is thought to be a good zone for surfers on intermediate level.

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