Numerical Investigation on Hydrodynamic Processes of Extreme Wave Groups on Fringing Reef

Abstract

The low-lying reef islands distributed in the tropical and subtropical coastal regions are highly vulnerable to the devastating damages of surges and waves during the severe weather events. Over the past two decades, extreme waves have caused tremendous loss and damages to the tropical and subtropical coastal regions. Previous research has focused on the wave hydrodynamics of tsunami waves, as well as regular and irregular waves on the fringing reefs. The complex wave hydrodynamics of extreme waves on the fringing reefs are rarely studied. By applying the nonhydrostatic numerical flow solver (NHWAVE), transformation and breaking process of the crest- and trough-focused wave groups on the fringing reef are analyzed in this study. Influences of the major factors, i.e., water depth, significant wave height, peak wave period, forereef slope and backreef slope, and ridge width, are discussed in detail. The results show that there are complex interactions between the fringing reef and the focused wave group. Breaking waves of high intensity can form at the reef crest. Meanwhile, due to the wave breakings at the reef crest and bottom friction of the reef flat, the local wave height can be effectively reduced. Within the complex wave hydrodynamics of focused waves on the fringing reef, most of the wave energy can be dissipated. In addition, hydrodynamic difference between the crest- and trough-focused waves on the fringing reef is very limited. The research results of this study will further help researchers to better understand the wave hydrodynamics of extreme waves over the fringing reefs.

Regulation of vegetation pattern on the hydrodynamic processes of erosion on hillslope in Loess Plateau, China

“…When rainfall occurs, the runoff from the upper slope generally converges on the lower slope due to an excess infiltration, and the energy and scouring force of the runoff, rills tend to develop first on the lower part of a long slope Shen et al 2015;Chang et al 2019;Luo et al 2020;Shi et al 2020;Niu et al 2020). This hydrodynamic erosion process involves the detachment of soil lumps, transport of soil particles, water storage and runoff, and soil water infiltration (Cui et al 2019;Qu et al 2022;Dang et al 2021). Wu et al (2014) indicated that soil particles will be detached from soil surface when the water shear stress is more than soil resistance through the research of relationship between runoff shear stress and soil detachment rate.…”

Influence of Excavation Pits on the Wave Hydrodynamics of Fringing Reefs under Regular Waves

“…Most of the existing studies primarily focus on analyzing the wave hydrodynamics of fringing reefs under regular waves [6,10], irregular waves [11][12][13], extreme waves [14,15], and tsunami-like waves [16]. Based on the field data, scholars systematically analyzed the wave breaking [17], wave setup, wave-induced current [18,19], and infragravity wave properties [20,21] of fringing reefs.…”