Study of irregular wave run-up over fringing reefs based on a shock-capturing Boussinesq model. (March 2019)

• Record Type: Journal Article
• Authors: Ning, Yue; Liu, Weijie; Zhao, Xizeng; Zhang, Yao; Sun, Zhilin
• Is Part Of: Applied ocean research. Volume 84(2019)
• Page Start: 216
• Page End: 224
• Publication Date: 2019-03
• Subjects: Fringing reefs -- Irregular wave -- Run-up -- Spectral components -- Boussinesq wave model; Ocean engineering -- Periodicals; 620.416205
• DOI: 10.1016/j.apor.2019.01.013
• Languages: English
• ISSNs: 0141-1187

Abstract

Abstract: This paper presents the results of a parametric study of irregular wave run-up over fringing reefs using the shock-capturing Boussinesq wave model Funwave-TVD to better understand the role of fringing reefs in the mitigation of wave-driven flooding. Laboratory experiments were newly performed with a typical fringing reef profile and typical hydrodynamic conditions to validate the model. Experimental data shows irregular wave run-ups are dominated by the low-frequency motions and confirms the run-up resonant phenomenon over the back-reef slope, which has been revealed in previous numerical studies. It is demonstrated that irregular wave evolution and run-up over fringing reefs are reasonably reproduced by the present model with a proper grid size. However, the infragravity run-up height and highest 2% run-up height over the back-reef slope are under-predicted due to the underestimation of the infragravity wave height over the reef flat. The validated model was then utilized to model irregular wave transformations and run-ups under different conditions. Through a series of numerical experiments, the effects of key hydrodynamic and reef geometry parameters, including the reef flat width, water depth over the reef flat, fore-reef slope angle and back-reef slope angle, on the irregular wave run-up were investigated. Variations of spectral components of irregular wave run-ups were examined to better understand the physical process underlying the effect of each parameter.