Numerical study on transient harbor oscillations induced by successive solitary waves
Numerical study on transient harbor oscillations induced by successive solitary waves
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连续孤立波诱发的瞬态港口振荡数值研究
DOI：
10.1007/s10236-017-1121-9
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发表时间：
2018
期刊：
影响因子：
2.3
通讯作者：
Gaidai Oleg
中科院分区：
文献类型：
--
作者：
Gao Junliang;Ji Chunyan;Liu Yingyi;Ma Xiaojian;Gaidai Oleg
海啸是行波，其特征是靠近海岸的波长长、振幅大。由于海啸的变形，波浪形涌浪在海岸带经常被观察到，可以被看作是一系列孤立波，具有不同的波高和不同的分离距离。本文首先研究了连续孤立波入射引起的瞬态港内振荡。瞬态振荡的模拟完全非线性Boussinesq模型，FUNWAVE-TVD。入射的连续孤立波包括双孤立波和三孤立波。本文主要研究了连续入射孤立波的不同波形参数对港内相对波能分布的影响。这些波浪参数包括入射波高、相邻波峰之间的相对间隔距离以及入射波列中的基元孤立波的数量。相邻波峰之间的相对分离距离被定义为入射波列中相邻波峰之间的距离与单个孤立波的有效波长的比值。文中还讨论了各种入射波激发的港内最大振荡。为了比较，也考虑了由单个孤立波激发的瞬态振荡。本文中所用的港口是假定为长而窄，有恒定的深度，自由表面运动的港口内基本上是一维的。研究表明，对于给定的港口和本文所研究的连续入射孤立波波形参数的变化范围，较大的入射波高和较小的入射海啸孤立波数量，导致港内相对波能分布较均匀。对于连续孤立波，相邻波峰之间的相对间距越大，不同共振模式下的相对波能分布波动越明显。当连续孤立波中的基元孤立波波高等于单个孤立波波高，且相邻波峰间的相对间距等于或大于0.6时，连续孤立波激发的港内最大振荡与单个孤立波激发的港内最大振荡几乎相同。
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 harbor used in this paper is assumed to be long and narrow and has constant depth; the free surface movement inside the harbor is essentially one-dimensional. This study reveals that, for the given harbor and for the variation ranges of all the waveform parameters of the incident successive solitary waves studied in this paper, the larger incident wave heights and the smaller number of elementary solitary waves in the incident tsunami lead to a more uniform relative wave energy distribution inside the harbor. For the successive solitary waves, the larger relative separation distance between adjacent crests can cause more obvious fluctuations of the relative wave energy distribution over different resonant modes. When the wave height of the elementary solitary wave in the successive solitary waves equals to that of the single solitary wave and the relative separation distance between adjacent crests is equal to or greater than 0.6, the maximum oscillation inside the harbor induced by the successive solitary waves is almost identical to that excited by the single solitary wave.