A note on the bimodal directional spreading of fetch‐limited wind waves
A note on the bimodal directional spreading of fetch‐limited wind waves
复制标题
关于取有限风波双峰定向传播的注记
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
M. Banner
中科院分区：
文献类型：
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作者：
I. Young;L. Verhagen;M. Banner
给出了有限风浪方向谱的测量结果。这些光谱的定向扩展函数是单峰的，并且在光谱峰值频率范围内最窄。与以前的测量一致，展宽的频率略高于或低于光谱峰值频率。然而，当频率大约是峰值频率的两倍时，单峰传播变成双峰传播，与风成一定角度传播的波能比沿着风向传播的能量更多。随着频率的增加，双峰旁瓣继续分离，并且幅度变大。用完全解非线性项的数值模型计算的结果表明，双峰结构是通过非线性波-波相互作用的能量定向转移来维持的。
Measurements of the directional spectra of fetch-limited wind waves are presented. The directional spreading functions for these spectra are unimodal and narrowest in the region of the spectral peak frequency. Consistent with previous measurements, the spreading broadens for frequencies just above and below the spectral peak frequency. At frequencies of approximately twice the peak frequency, however, the unimodal spreading becomes bimodal, and more wave energy propagates at an angle to the wind than in the wind direction. The bimodal sidelobes continue to separate with increasing frequency and become larger in magnitude. Results obtained with a numerical model with a full solution to the nonlinear terms indicate that the bimodal structure is maintained by directional transfer of energy through nonlinear wave-wave interactions.