Field Observation and Numerical Modelling on the Hydrodynamics Behind a Submerged Breakwater

• Published in: Journal of coastal research 2017-01, Vol.79 (sp1), p.304-308
• Main Authors: Kim, In Ho, Kim, Jinhoon, Jeong, Yeon-Myeong, Hur, Dong Soo, Shin, Sungwon
• Format: Article
• Language: English
• Subjects: Bathymetry; Beach erosion; Beaches; Breakwalls; Breakwaters; Construction contracts; crescentic sand bar; field observation; Fluid mechanics; Hydrodynamics; Mathematical models; Modeling; numerical modeling; Observational research; Researchers; Rip current; Sand & gravel; Shorelines; Simulation; Simulations; Soil erosion; Studies; Submerged; Three dimensional modeling; Topography; Turbulence; Turbulent flow; Typhoons; UNDERSTANDING OF WATERSHED AND COASTAL ENVIRONMENT; Wave height; Wave power; Waves
• ISSN: 0749-0208; 1551-5036
• DOI: 10.2112/SI79-062.1

Kim, I.H.; Kim, J.; Jeong, Y.-M.; Hur, D.S., and Shin, S., 2017. Field observation and numerical modelling on the hydrodynamics behind a submerged breakwater. 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. 304–308. Coconut Creek (Florida), ISSN 0749-0208. In 2014, a submerged breakwater installed near the erosion hot spot and the beach is being formed to salient beach behind the structure at Anmok beach, which is located on the east coast of Korea. The field monitoring has been carried out for past three years in order to investigate the change of beach morphology and shoreline before and after the breakwater construction. Wave gages were installed in the offshore location, in front of the breakwater and in the behind of the breakwater to investigate the wave height variation. A three-dimensional numerical model based on the Navier-Stokes equation with a Large Eddy Simulation (LES) turbulence closure scheme (LES-WASS-3D) was employed to predict the hydrodynamics near the submerged breakwater. The model used the beach topography and the bottom bathymetry before the breakwater construction to predict the wave transformation, refraction and diffraction due to the installation of the breakwater. The model simulated the wave and nearshore current fields especially behind the submerged breakwater and successfully predicted the wave heights near the submerged breakwater in high correlation (r2 = 0.98) with the filed observation results. The numerical results also showed that the predicted wave and current fields could induce the sediment deposition behind the structure.