المؤلفون: Haegyun Lee

المصدر: Journal of Coastal Research. 114

مصطلحات موضوعية: Ecology, Wave propagation, Computation, Mathematical analysis, Parallel algorithm, Compressibility, Conical surface, Solver, Navier–Stokes equations, Geology, Finite element method, Earth-Surface Processes, Water Science and Technology

الوصف: Lee, H., 2021. Propagation of solitary wave around conical island in level-set finite element framework. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 16–20. Coconut Creek (Florida), ISSN 0749-0208. Though the solitary wave is a single wave, it consists of a complex spectrum of frequencies, which enables in-depth analysis and reliable generation both in the laboratory and in the numerical model. For these reasons, solitary waves are known to be a good candidate for the description of waves including tsunamis since they effectively model the important effects of the long wave on the coasts very well. In addition, it is supposed to propagate over constant depth without appreciable changes, allowing for consistent referencing of its offshore or incident wave height. In this study, the level-set scheme, which is combined with the incompressible Navier-Stokes solver based on the fractional step algorithm in the framework of the finite element method, was applied to the modeling of wave propagation and runup on a circular conical island. Unstructured hexahedral meshes were generated for this purpose and MPI (Message Passing Interface) based parallel algorithms were developed to accelerate the computation. The physical behavior of waves are discussed in detail and the numerical results (e.g., runup heights) are compared with the experimental data. The good agreements were observed.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::1dbeaf46050d0e6f9bd6936890bb1bddTest
https://doi.org/10.2112/jcr-si114-004.1Test

المؤلفون: Woo Dong Lee, Tak Kee Lee, Choonghyun Kang, Sungnam Hong, Jooyong Lee

المصدر: Journal of Coastal Research. 114

مصطلحات موضوعية: Dive profile, Ecology, Wave propagation, Decompression, business.industry, Computational fluid dynamics, Wave loading, Wave height, Wind wave, Underwater, business, Geology, Earth-Surface Processes, Water Science and Technology, Marine engineering

الوصف: Lee, W.D.; Kang, C.; Hong, S.; Lee, T.K., and Lee, J., 2021. Effect of wave load on decompression of underwater workers: CFD-VPM simulation. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 614–618. Coconut Creek (Florida), ISSN 0749-0208. Hydrodynamic pressure from cyclic wave action causes water pressure increases and vibration, and these pressure changes can have a significant impact on underwater workers in high-pressure environments. This study investigated the impact of wave loading on decompression procedures for underwater workers using a coupled CFD-VPM. Computational Fluid Dynamics (CFD) were used to simulate wave propagation, and the Varying Permeability Model (VPM) was used to simulate the dive profile. Results of the wave propagation simulation showed that wave height and nonlinearity increased due to shoaling when approaching a beach, and the period was shortened. The maximum dynamic pressure head exceeded 1 m at depths less than 45 m and reached 10.3 m at a depth of 3 m. Simulations of the dive profile revealed that decompression time increased by 11 m and 9 s (28.36 %) under extraordinary wave conditions when underwater work was performed for 2 hours at a depth of 20 m. Furthermore, decompression time increased by 12 min and 40 s (10 %) at a working depth of 30 m. For safe underwater work operations under extraordinary wave conditions, decompression procedures should account for the pressure rise and vibration caused by wave action.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::e6c1eccd40ea4f0fa85c33080c8eeca5Test
https://doi.org/10.2112/jcr-si114-124.1Test

المؤلفون: Sang Myeong Oh, Hanna Kim, Young Ho Kim, Kyeong Ok Kim, KiRyong Kang

المصدر: Journal of Coastal Research. 114

مصطلحات موضوعية: Ecology, Meteorology, Buoy, Wave propagation, Dissipation, Physics::Geophysics, Wave model, Data assimilation, Environmental science, Satellite, Significant wave height, Physics::Atmospheric and Oceanic Physics, Earth-Surface Processes, Water Science and Technology, Interpolation

الوصف: Kim, H.; Kim, Y.H.; Oh, S.M.; Kang, K., and Kim, K.O., 2021. Application of data assimilation for spectral wave model in coastal regions of South Korea. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 76–80. Coconut Creek (Florida), ISSN 0749-0208. The primary factor determining the accuracy of wave simulation is the accuracy of the wind data, which represents the main force of wave generation. Its accuracy also depends on the optimality of parameters related to the growth, dissipation of wave energy and nonlinear energy transfer between wave components. Wave models have limitations due to errors of wind fields and a lack of understanding of wave dynamics such as white capping dissipation, wave-bottom interaction processes and long-term wave propagation. This paper investigates the performance of a wave model based on WAVEWATCH III (WW3) version 6.07 equipped with spectral wave data assimilation using the optimal interpolation (OI) method, which updates the spectral wave energy of the model by assimilating the observed significant wave height. Data assimilation was applied for the coastal region of Korea using near real-time global satellite wave observation data provided by the Copernicus Marine Environment Monitoring Service (CMEMS) and the buoy data of the Korea Meteorological Administration (KMA). The verification of the model was done by comparing simulated results with observations by KMA buoys, which suggests the successful application of the data assimilation to improve the model accuracy.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::16ee954715e9f6641ad074cdbcb2c54aTest
https://doi.org/10.2112/jcr-si114-016.1Test

المؤلفون: Eun-Hong Min, Weoncheol Koo

المصدر: Journal of Coastal Research. 114

مصطلحات موضوعية: Darcy's law, Ecology, Wave propagation, Attenuation, Mechanics, Physics::Geophysics, Nonlinear system, Boundary value problem, Time domain, Boundary element method, Geology, Seabed, Earth-Surface Processes, Water Science and Technology

الوصف: Min, E.-H. and Koo, W., 2021. Numerical analysis of nonlinear wave characteristics under porous sloped-seabed conditions. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 116–120. Coconut Creek (Florida), ISSN 0749-0208. The characteristics of nonlinear wave attenuation were analyzed under porous sloped-seabed conditions. Nonlinear wave propagation was simulated in the time domain using a two-dimensional fully nonlinear numerical wave tank (NWT). The NWT technique was based on the boundary element method and consisted of two computational domains: A fluid domain and a porous seabed domain. To account for the wave-porous subsea interaction, the boundary value problem was solved in each domain, and the calculated values were exchanged at the interface boundary between the fluid domain and the porous domain at each time step. The shoaling coefficients for wave propagation on a sloped-seabed were calculated, and the attenuation of the waves due to interaction with the porous bottom was investigated. Waves traveling to the coast were decomposed into each frequency component, and the magnitude of the wave attenuation ratio for each component was compared. The characteristics of wave propagation according to the permeability coefficients on the seabed, wave steepness, and wave periods were also investigated.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::7c422d07850a3ceef5dafcf85e838e00Test
https://doi.org/10.2112/jcr-si114-024.1Test

المؤلفون: Yong-Sik Cho, Khawar Rehman, Koo Young Park

المصدر: Journal of Coastal Research. 85:1111-1115

مصطلحات موضوعية: Finite volume method, Ecology, Discretization, Wave propagation, Breaking wave, 02 engineering and technology, 01 natural sciences, 010305 fluids & plasmas, Flume, 020303 mechanical engineering & transports, 0203 mechanical engineering, Breakwater, 0103 physical sciences, Shallow water equations, Geology, Earth-Surface Processes, Water Science and Technology, Swash, Marine engineering

الوصف: Rehman, K.; Park, K.-Y., and Cho, Y.-S., 2018. Experimental and Numerical Investigation of Solitary Wave Run-up Reduction. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1111–1115. Coconut Creek (Florida), ISSN 0749-0208.Rising sea-levels and extreme wave events threaten coastal communities and stability of coastal regions. Accurate prediction of wave over-topping over coastal protection structures is challenging, but vital for effective hazard mitigation. Non-hydrostatic numerical modelling and laboratory experiments are used to assess magnitude of run-up over coastal protection structures under varying relative wave heights and structural features. The primary focus is the investigation of solitary wave impact with breakwaters, the consequent run-up and measures for its reduction. The experiments consisted of generating solitary waves in a 1.1 m high and 32.5 m long flume and observing its run-up for different heights of incident waves. A slope adjuster was used to vary the slope of a plywood plank for reproducing coastal features. Experimental observations were verified by proposing a numerical model based on non-linear shallow water equations (NLSWE) and solution is obtained by Godunov-type finite volume method. The NLSWE provide good approximation of shoaling, wave breaking, and wave reflection which arise due to wave overtopping in the swash and surf zones. The novel feature of the numerical model is the introduction of bed slope discretization technique – applicable on both structure and unstructured meshes- which offers well-balanced solution even for steep slopes encountered in case of breakwaters. Shock-capturing capabilities of Harten, Lax, and van Leer with contact wave restoration (HLLC) solver are utilized for accurate estimation of shocks and bore waves features during flow transitions. The proposed model gives excellentn agreement with experimental observations. The findings will further enhance the understanding of extreme wave propagation events over submerged coastal structures and related mitigation techniques.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::3db92dec6b327ff9bd86872ffb15be16Test
https://doi.org/10.2112/si85-223.1Test

المؤلفون: Jooyong Lee, Won Chul Cho, Hyun Seung Kim, Jung Won Kim, Jung Lyul Lee

المصدر: Journal of Coastal Research. 85:706-710

مصطلحات موضوعية: Shore, geography, geography.geographical_feature_category, Ecology, Wave propagation, Prediction system, Swell, Peninsula, Typhoon, Wind wave, Seismology, Rip current, Geology, Earth-Surface Processes, Water Science and Technology

الوصف: Lee, J.L.; Kim, J.W.; Kim, H.S.; Cho, W.C., and Lee, J., 2018. Development of prediction system for invasion of swell-like waves on the southern coast of Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 706–710. Coconut Creek (Florida), ISSN 0749-0208.Recently, several drowning accidents caused by rip currents were reported along Haeundae Beach, located at the southeastern corner of the Korean Peninsula. Several dozen people were swept away by rip currents, and subsequently rescued between August 7 and 10, 2012. The main cause of rip currents is swell waves that approach the shore. The rip current becomes more dangerous when a relatively long-period swell-like wave invades and is intensified, during the passage of typhoons far off shore. However, existing wind wave models require significant computational cost and time to obtain solutions to a set of partial differential equations, and have low accuracy for predicting the invasion of swell-like waves on coasts because they simultaneously calculate wind wave generation and wave propagation. In this study, we used a fractional step method to solve the wind wave generation and swell wave propagation components, in which the former is simulated using a typical spectrum approach and the latter is simulated using a Lagrangian approach. The results from the theoretical model were compared with field data collected during the dangerous rip current events in August 2012.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::613c68197a9eae21a8d67c9da68c6676Test
https://doi.org/10.2112/si85-142.1Test

المؤلفون: Weoncheol Koo, Eun-Hong Min

المصدر: Journal of Coastal Research. 85:966-970

مصطلحات موضوعية: Darcy's law, Ecology, Computer simulation, Wave propagation, 020101 civil engineering, 02 engineering and technology, Mechanics, 01 natural sciences, Physics::Geophysics, 010305 fluids & plasmas, 0201 civil engineering, Permeability (earth sciences), Amplitude, 0103 physical sciences, Time domain, Boundary value problem, Boundary element method, Geology, Earth-Surface Processes, Water Science and Technology

الوصف: Min, E.-H. and Koo, W., 2018. Numerical simulation of wave propagation over structures on a porous seabed. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 966–970. Coconut Creek (Florida), ISSN 0749-0208. A wave-body interaction with semi-circular rigid structures placed on a porous seabed was simulated. Owing to the rigid structures installed at regular intervals, spatial modulation of the wave propagation due to a Bragg reflection was examined. The computational domain consisted of a potential-flow water domain and porous domain with Darcy's law interface boundary condition. Using the numerical wave tank technique, the two-domain boundary element method was developed to simulate wave propagation over seafloor structures on the porous boundary in the time domain. For various permeability constants and incident wave frequencies, wave amplitude was var...

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::247def832aa03e66e84364264b0e2ae5Test
https://doi.org/10.2112/si85-194.1Test

المؤلفون: Hitoshi Tanaka, Nguyen Trung Viet, Dinh Van Duy, Yuta Mitobe

المصدر: Journal of Coastal Research. 85:621-625

مصطلحات موضوعية: Shore, geography, geography.geographical_feature_category, Ecology, Wave propagation, Geomorphology, Geology, Earth-Surface Processes, Water Science and Technology, Accretion (coastal management), Coastal erosion

الوصف: Tanaka, H.; Duy, D.V.; Mitobe, Y., and Viet, N.T., 2018. Theory for Erosion Wave Propagation in Cua Dai Beach, Vietnam. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 621–625. Coconut Creek (Florida), ISSN 0749-0208.This paper deals with the propagation of erosion wave in Cua Dai Beach in Central Vietnam under the influence of longshore sediment movement using analytical results from the simplified equation of the one-line model. In addition, measured shoreline positions obtained from Landsat images are utilized to validate the calculated results. Effects of the waves on the shapes of the erosion/accretion zones along the Cua Dai Beach are observed. Using the analytical solutions, the propagation speed of the erosion wave is estimated as 37 m/y while this value is 54 m/y in reality. Coastal structures such as seawalls located along the Cua Dai Beach is causing more severe erosion along Cua Dai Beach.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::df7aa8de7caad57eea829bbde21f1c58Test
https://doi.org/10.2112/si85-125.1Test

المؤلفون: Álvarez-Ellacuria, Amaya, Orfila, Alejandro, Olabarrieta, Maitane, Medina, Raúl, Vizoso, Guillermo, Tintoré, Joaquín

مصطلحات موضوعية: Rip currents, Wave propagation, Surf zone currents generation, Beach hazards

الوصف: 7 páginas, 6 figuras. ; [EN]An operational forecasting system for nearshore waves and wave-induced currents is presented. The forecasting system (FS) has been built to provide real time information about nearshore conditions for beach safety purposes. The system has been built in a modular way with four different autonomous submodels providing, twice a day, a 36-hour wave and current forecast, with a temporal resolution of 1 hour. Making use of a mild slope parabolic model, the system propagates hourly deep water wave spectra to the shore. The resulting radiation stresses are introduced in a depth-integrated Navier-Stokes model to derive the resulting current fields. The system has been implemented in a beach located in the northeastern part of Mallorca Island (western Mediterranean), characterized by its high touristic pressure during summer season. The FS has been running for 3 years and is a valuable tool for local authorities for beach safety management. ; [ES]En este trabajo se presenta un sistema operacional para la predicción de las corrientes generadas por la rotura del oleaje en aguas someras. El sistema se ha desarrollado con el propósito de proporcionar las condiciones de oleaje y corrientes para la seguridad en playas. El sistema está construido en forma modular con cuatro submodelos funcionando de forma autónoma para proporcionar el oleaje y las corrientes dos veces al día con un horizonte predictivo de 36 horas. Las condiciones de oleaje en aguas profundas, se propagan hasta la costa mediante un modelo parabólico de pendiente suave y los tensores de radiación resultantes se introducen como forzamiento en un modelo de Navier Stokes verticalmente integrado. El sistema se ha aplicado en una zona piloto en la Isla de Malloca (Mediterráneo occidental). El sistema ha estado funcionando ininterrumpidamente durante tres años habiéndose mostrado como una herramienta muy válida para la gestión de la seguridad en la playa por parte de las Autoridades. La extensión del sistema a otras áreas del litoral es ...

العلاقة: http://dx.doi.org/10.2112/08-1133.1Test; Journal of Coastal Research 26 (3) : 503-509 (2010); http://hdl.handle.net/10261/48647Test

الإتاحة: https://doi.org/10.2112/08-1133.1Test
http://hdl.handle.net/10261/48647Test

المؤلفون: Young-Kwang Choi, Seung-Nam Seo

المصدر: Journal of Coastal Research. 79:354-358

مصطلحات موضوعية: Disturbance (geology), 010504 meteorology & atmospheric sciences, Ecology, Discretization, Shock (fluid dynamics), Meteorology, Atmospheric pressure, 010505 oceanography, Wave propagation, Mechanics, 01 natural sciences, Riemann solver, Waves and shallow water, symbols.namesake, Edge wave, symbols, Physics::Atmospheric and Oceanic Physics, Geology, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology

الوصف: Choi, Y.-K. and Seo, S.-N., 2017. Shock capturing shallow water model for long waves generated by a moving atmospheric pressure. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 354–358. Coconut Creek (Florida), ISSN 0749-0208. The shock capturing numerical model based on nonlinear shallow water equations is developed to predict run-up as well as edge waves generated by a moving atmospheric pressure disturbance across a straight shoreline on a sloping beach. The HLL approximate Riemann solver with the fifth order accurate WENO scheme is used to compute numerical flux in spatial discretization, which yields better results in comparison with TVD-MUSCL type schemes. Numerical experiments are conducted for wave propagation by a moving atmospheric pressure disturbance normally approaching the coastline. When the atmospheric pressure disturbance suddenly acts on the water surface...

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::18852e857476669d4bd1179514aa251dTest
https://doi.org/10.2112/si79-072.1Test