摘要: |
本文用摄动方法导出了均匀水底上精确至二阶的二维随机波动解。依据此解并将二阶谱定义为三阶矩函数的Fourier变换,首次给出了精确至二阶的二维随机波面二阶谱的理论表达式并简略地考虑了它的各个组成部分的物理意义。 |
关键词: 随机海浪 非线性 二阶谱 |
DOI: |
分类号: |
基金项目:国家自然科学基金资助项目,49070254号 |
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BISPECTRA OF TWO-DIMENSIONAL RANDOM WAVES IN WATER OF UNIFORM DEPTH |
Sun Fu1, Ding Pingxing2, Yu Zhouwen3
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1.Laboratory of Physical Oceanography, Ocean University of Qingdao, 266003;2.Institute of Estuarine and Coastal Research, East China Normal University, Shanghai 200062;3.Department of Science and Technology, Slate Oceanic Administration, Beijing 100860
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Abstract: |
By means of perturbation method, solutions exact to the second order are strictly deduced for two-dimensional random waves in water of arbitary uniform depth. Based on the solutions, the theoretical expression of bispectra is given for the first time, which is written as follows:
(For the equations please see the PDF file.)
It may be seen from the above that the bispectra of surface elevation are composed of three parts, which respectively describe the interaction between two free waves of the frequencies ω and ω', and between one secondary forced wave of the frequency ω + ω' and the two free waves.
The results presented in this paper might be an essential development for applying bispectral analysis to the study of the nonlinearity of the sea waves. |
Key words: Random waves, Nonlinearity, Bispectra |