中文摘要：

该文采用完全非线性Boussinesq方程，模拟波群引起的港内二阶长波振荡的现象，研究了短波对港池振荡的影响。发现：并非所有波群都可以引起港内长周期振荡，而只有短波波长与港口宽度之比大于3．3时港内才会出现明显的二阶长波振荡。且在某些条件下，港内二阶长波的波幅可以达到与短波相同的量值。通过基于小波变换下的自相关系数谱分析发现，港池振荡时港内各次谐波间存在着复杂的非线性能量传递。

英文摘要：

The second-order low-frequency oscillations inside a rectangular harbor induced by different wave groups with the same resonance frequency are simulated by the full nonlinear Boussinesq model. It is found that low-frequency oscillations could be evidently excited only when the ratio of the short wavelength to the harbor entrance is greater than 3.3. The second-order wave could be as large as the first-order wave inside the harbor. The paper interprets this phenomenoncan from the interactions beteen short waves and the harbor entrance. The wavelet-based bicoherence spectrum is employed to analyze the wave-wave interactions. It is shown that the second-order long wave not only participates in wave-wave interactions between the carrier short waves but also takes part in interactions between super-harmonic wave components.