基于小波理论的舰船非线性横摇运动特性分析

探索采用小波分析方法研究船舶在波浪中非线性摇摆运动的动力学特性．对在几种不同的典型波浪参数情况下，得到的船舶在波浪中非线性摇摆的响应，进行小波变换．利用小波变换所特有的时频窗，可以同时在时域和频域中研究船舶横摇响应的模图和相图．通过分析所得模图和相图的典型特征，得到舰船非线性横摇幅值和频率等动力学特性．且小波变换适应不同频率的窗口特性具有更好的分辨率，可以获得更多的横摇运动响应特性信息．研究表明，小波分析在非线性横摇运动动力学特性分析的研究中是可行的，可以加强对船舶横摇非线性复杂动力学特性的分析能力．

Analysis on the Nonlinear Dynamical Character of Ship Rolling Based on Wavelet Theory

Wavelet theory was exploringly used to investigate the nonlinear dynamic characteristics of ship roll motion in waves. Wavelet transform was applied to the roll responses of ship in waves. The features of modulus and phase of wavelet transform of rolling response were analyzed via a time-frequency window of the wavelet transform. The dynamic characters about amplitude and frequency of ship nonlinear roll under typical wave parameters were obtained. And more information about characteristics of ship rolling can be obtained because of the higher resolution of variable-sized windowing technique of wavelet transform. The investigation not only highlights the feasibility of using wavelet transform in the analysis of nonlinear dynamic characteristics of ship rolling in waves, but also shows how it could enhance the analysis abilities.