A Numerical Study on the Responses of Wave-Driven Circulation to Varying Incident Wave Forcing and Reef Morphology in A Reef-Lagoon-Channel System

• Published in: China ocean engineering Vol. 36; no. 6; pp. 933 - 946
• Main Authors: Yao, Yu, Wu, Ji, Li, Jiang-xia, Chen, Long
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2022; Springer Nature B.V; Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province,Changsha 410114,China%School of Hydraulic and Environmental Engineering,Changsha University of Science and Technology,Changsha 410114,China; School of Hydraulic and Environmental Engineering,Changsha University of Science and Technology,Changsha 410114,China
• Subjects: Boussinesq approximation; Boussinesq equations; Coastal Sciences; Empirical equations; Engineering; Environmental impact; Fluid- and Aerodynamics; Geomorphology; Incident waves; Laboratories; Lagoons; Marine & Freshwater Sciences; Mathematical models; Morphology; Numerical and Computational Physics; Numerical models; Oceanography; Offshore Engineering; Original Paper; Parameters; Reefs; Roughness; Simulation; Wave height; Wave period; Width; wave-induced setup; Boussinesq equations; coral reef; circulation cell; wave pump efficiency
• DOI: 10.1007/s13344-022-0082-z
• ISSN: 0890-5487

Wave-driven circulation in a reef-lagoon-channel system has significant ecological, geomorphological, and environmental implications. However, there is still research gap in fully understanding the responses of wave-driven circulation in the system to varying incident wave forcing and reef morphology. To better interpret the wave-current process inside an idealized reef-lagoon-channel configuration, a numerical model based on the horizontally two-dimensional (2DH) fully nonlinear Boussinesq equations is presented in this study. The adopted model is firstly validated by a published laboratory dataset for wave height, wave setup and mean current in the system. Subsequently, the impacts of wave forcing (incident wave height, incident wave period, reef-flat wave level) and reef morphological (fore-reef slope, cross-shore reef-flat width, channel width, reef roughness) factors that are not fully considered in the previous laboratory studies are reported through the numerical simulations in this study. Finally, the model is applied to analyze the wave pump efficiency parameter in the system, and an empirical equation to predict this parameter is also proposed.