Analysis of higher harmonics in a focused water wave group by a nonlinear potential flow model
Analysis of higher harmonics in a focused water wave group by a nonlinear potential flow model
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非线性势流模型分析聚焦水波群中的高次谐波
DOI：
10.1016/j.oceaneng.2019.106581
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发表时间：
2019
影响因子：
5
通讯作者：
Feng X
中科院分区：
文献类型：
--
作者：
Feng X
本文基于stokes型非线性结构的假设，分析了聚焦波群的高次谐波高程。新波理论采用完全非线性势流模型生成非线性波群，它代表了随机海况下的一个极端事件。我们提出了一种在数值波槽中产生高质量的窄带波谱非线性波群的方法。采用相位处理方法精确提取高次谐波高度。高程谱显示出前四次谐波的清晰分离。与实验数据的比较表明，高次谐波的一致性非常好。我们证实了聚焦波群中谐波高程的stokes型底层非线性结构。这是通过模拟不同波浪陡度的波浪群，计算相应的高次谐波高程系数得到的。谐波系数对于不同的陡度几乎是恒定的。非线性波高程的stokes型结构的一个含义是，它允许我们仅基于线性分量来估计高次谐波。通过使用线性NewWave模型和其高次谐波系数重建非线性聚焦波群，成功地证明了这一点。
This work analyses the higher harmonic wave elevations of focused wave groups based on the assumption of a Stokes-type nonlinear structure. A fully nonlinear potential flow model is employed to generate nonlinear wave groups by the NewWave theory, which represents an extreme event in a random sea state. We present a methodology to generate high-quality nonlinear wave groups of a narrow-banded wave spectrum in a numerical wave tank. A phase-manipulation approach is employed to accurately extract the higher harmonic elevations. The elevation spectra show clean separation of the first four harmonics. Comparisons with the experimental data show remarkably good agreements for the higher harmonics. We confirm the Stokes-type underlying nonlinear structure of the harmonic elevations in focused wave groups. This is found by simulating wave groups with varying wave steepness and calculating the corresponding elevation coefficients of the higher harmonics. The harmonic coefficients are found almost constant against varying steepness. An implication of the Stokes-type structure for the nonlinear wave elevations is that, it allows us to estimate the higher harmonics based only on the linear component. This is successfully demonstrated by reconstructing a nonlinear focused wave group using the linear NewWave model and the coefficients at its higher harmonics.
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影响因子：
4.4
作者：
C. Whittaker;A. Raby;C. J. Fitzgerald;P. Taylor
通讯作者：
C. Whittaker;A. Raby;C. J. Fitzgerald;P. Taylor
关于修正的非线性 Schr
DOI：
--
发表时间：
2011
期刊：
影响因子：
--
作者：
J. DiFranco;P. Miller;B. Muite
通讯作者：
B. Muite
相位分解在波盆试验随机时间序列分析中的应用
DOI：
10.1115/omae2019-95172
发表时间：
2019
期刊：
--
影响因子：
--
作者：
Adcock T
通讯作者：
Adcock T
DOI：
--
发表时间：
2015
期刊：
影响因子：
--
作者：
A. Richards
通讯作者：
A. Richards