摘要港湾振荡在海岸工程领域中是一个历史悠久且至关重要的研究方向。国内外的很 多港口都曾观测到港湾振荡现象，这极大地影响了港内工作效率和船舶的系泊安全。 本文首先介绍了研究背景和研究港湾共振的重要性，列举了近年来发生的一系列的港 湾振荡事故，然后介绍了本文使用的模拟入射波浪的数值模型—FUNWAVE-TVD 模 型及预测港湾的本征频率和本征模态的方法—正交模态分解法。随后，使用该数值模 型和正交模态分解法研究了孤立波和 N 波诱发的港湾共振。研究发现：79094

1。 孤立波入射时，港内的总波能并不只随着平均水深的增加而单调增加，其影响 因素还有底部剖面的形状。港内的相对波能分布极大地受到入射孤立波波高的影响。 并且入射孤立波波高越大则港内相对波能分布越趋向于均匀，但底部剖面形状对波能 分布的影响却微乎其微。

2。 N 波入射时，港内相对波能分布与入射 N 波波幅紧密相关。当入射波波幅较小 时，港内波能主要集中在最低的几个共振模态上。随着入射波波幅的增大，分布于更 高模态上的波能的比重增加，港内波能的分布趋于均匀，并且占有最大波能的共振模 态逐渐由较低的模态向较高的模态转移。此外， MS 型 N 波诱发的港湾共振的港内波 能分布比 TS 型更加集中。

关键词：港湾振荡；FUNWAVE-TVD 模型；正交模态分解法;  孤立波；N 波

Abstract

Harbor resonance is a traditional and vital research orientation in the field of coastal engineering。 This phenomenon has been observed in many harbors at home and abroad, which has a bad effect on the work efficiency of the harbor and safety of the ship berthed at the harbor。 First of all, this dissertation introduces the research background and the importance of researching the harbor resonance。 Then the FUNWAVE-TVD model which is used to simulate the incident wave is introduced, so is the normal mode decomposition (NMD)。 Subsequently, using the FUNWAVE-TVD model and the NMD, the harbor resonances induced by the solitary wave and the N-wave are discussed。 Here are the conclusions:

1。When the solitary wave propagates into the harbor, the total wave energy inside the harbor doesn’t monotonically increase with respect to the mean water depth, the bottom profile is another influence factor。 The distribution of the relative wave energy is affected by the wave height of the incident solitary wave。 Along with the increase of the wave height, the wave energy distribution tends to be more and more uniform, but the effect of the bottom profile on it is trivial。

2。When the N-wave propagates into the harbor, the wave amplitude makes a giant effect on the distribution of the wave energy inside the harbor。 When the wave amplitude is small, most of the wave energy inside the harbor focuses on the lowest few resonant modes。 Along with the increase of the wave height, the wave energy tends to focus on higher resonant modes。 In addition, the type of the N-wave also makes great effect on the distribution of the wave energy。 The wave energy induced by the MS-type N-wave is more concentrated than that of the TS-type N-wave。

Keywords: Harbor resonance; the FUNWAVE-TVD model; Normal mode decomposition method; Solitary wave; N-wave

目 录

第一章 绪论 1

1。1  研究背景 1

1。2  港湾振荡的概念、特征和产生机制