Numerical study on transient harbor oscillations induced by successive solitary waves

Abstract

Tsunamis are traveling waves which are characterized by long wavelengths and large amplitudes close to the shore. Due to the transformation of tsunamis, undular bores have been frequently observed in the coastal zone and can be viewed as a sequence of solitary waves with different wave heights and different separation distances among them. In this article, transient harbor oscillations induced by incident successive solitary waves are first investigated. The transient oscillations are simulated by a fully nonlinear Boussinesq model, FUNWAVE-TVD. The incident successive solitary waves include double solitary waves and triple solitary waves. This paper mainly focuses on the effects of different waveform parameters of the incident successive solitary waves on the relative wave energy distribution inside the harbor. These wave parameters include the incident wave height, the relative separation distance between adjacent crests and the number of elementary solitary waves in the incident wave train. The relative separation distance between adjacent crests is defined as the ratio of the distance between adjacent crests in the incident wave train to the effective wavelength of the single solitary wave. Maximum oscillations inside the harbor excited by various incident waves are also discussed. For comparison, the transient oscillation excited by the single solitary wave is also considered. The

Effects of offshore fringing reefs on the transient harbor resonance excited by solitary waves

“…It is formulated and solved as a multidimensional optimization problem, in which the eigenfrequencies and eigenmodes predicted in the first step are utilized as known variables. Subsequently, the NMD method was improved by Gao et Recently, by adopting this data analysis technique, the wave energy distributions inside the harbor during transient oscillations triggered by different types of tsunamis, including solitary waves, Nwaves and successive solitary waves, were comprehensively analyzed in Gao et al (2017a;2016b;2018a). For the detailed theory on the NMD method, the interested reader is referred to Sobey (2006) and Gao et al (2015).Similar to Gao et al (2017a;2016b;2018a), all numerical simulations in this article also utilize this method to analyze the wave energy distribution inside the harbor excited by incident solitary waves.…”

“…Recently, by using a fully nonlinear Boussniesq model, Gao et al (2016b;2016c) performed investigations on the transient harbor resonance induced by solitary waves. More recently, the transient harbor oscillations induced by other two types of tsunami waveforms (i.e., N-waves and successive solitary waves) were further investigated by Gao et al (2017a;2018a).…”

Study on Influences of Fringing Reef on Harbor Oscillations Triggered by N-Waves

“…As certain characteristics of real tsunamis (e.g., the stable hump-like waveform) is able to be represented by solitary waves very well, numerous existing studies have adopted solitary waves to mimicking tsunamis for decades (Ning et al, 2019;Synolakis, 1987). Heretofore, investigations on the tsunami-induced harbor resonance are also mostly restricted to utilizing a solitary wave (e.g., Dong et al (2020a); Gao et al (2019a)) or successive solitary waves (e.g., Gao et al (2018a;).…”

Numerical investigation of harbor oscillations induced by focused transient wave groups

“…The resonance inside a harbor increases considerably before the energy input from the external oceanic waves is balanced by energy losses caused by boundary absorption, bottom friction, and radiation from the entrance (e.g., Chen et al (2006); Gao et al (2017b); Gao et al (2018b); Kumar and Gulshan (2018); Losada et al (2008); Rupali et al (2020); Wang et al (2011); Wang et al (2014)). The transient resonance inside a harbor is mainly triggered by transient long waves, such as various types of tsunami waves including solitary waves, N-waves, and successive solitary waves (Dong et al, 2010a;Gao et al, 2018a). When the transient long waves impact on the harbor, the resonance does not experience a prolonged growth stage and immediately attains its maximum value (Dong et al, 2010a).…”