Revisiting wind wave growth with fully coupled direct numerical simulations
Revisiting wind wave growth with fully coupled direct numerical simulations
复制标题
通过全耦合直接数值模拟重新审视风浪的增长
DOI：
10.1017/jfm.2022.822
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发表时间：
2022
影响因子：
3.7
通讯作者：
Deike, Luc
中科院分区：
文献类型：
--
作者：
Wu, Jiarong;Popinet, Stéphane;Deike, Luc
本文通过求解两相Navier-Stokes方程的直接数值模拟研究了风浪的增长。我们考虑波速比从0.1到0.3;这两个是独立变化的。湍流风和旅行，几乎单色波完全耦合没有任何亚网格尺度模型。壁面摩擦雷诺数为720。新的完全耦合的方法捕获的波的振幅和形状的同时演变，连同水下边界层（漂移电流），波浪破碎。由随时间变化的表面高程计算的波能增长与由表面压力分布计算的波能增长在定量上是一致的，这证实了压力强迫对有限振幅重力波的主导作用。本文系统地报道了海面压力分布主模的相移和振幅，为可能的风浪增长理论提供了直接的证据。间歇性和局部气流分离观察到的陡峭的波与小波龄，但它的效果设置的相位平均压力分布是没有显着不同的非分离的庇护。结果表明，波浪拖曳力不是波龄的强函数，而与波陡密切相关。此外，由于波浪的波峰形状等复杂的耦合作用，风浪耦合的历史也会对波浪阻力产生影响。我们得到的标准化波增长率与以前的研究一致。我们努力澄清各种普遍采用的基本假设，并调和不同的以前的理论，数值和实验结果之间的数据的分散，因为我们重新审视这个长期存在的问题与新的数值证据。
We investigate wind wave growth by direct numerical simulations solving for the two-phase Navier–Stokes equations. We consider the ratio of the wave speed from 0.1 to 0.3; the two being varied independently. The turbulent wind and the travelling, nearly monochromatic waves are fully coupled without any subgrid-scale models. The wall friction Reynolds number is 720. The novel fully coupled approach captures the simultaneous evolution of the wave amplitude and shape, together with the underwater boundary layer (drift current), up to wave breaking. The wave energy growth computed from the time-dependent surface elevation is in quantitative agreement with that computed from the surface pressure distribution, which confirms the leading role of the pressure forcing for finite amplitude gravity waves. The phase shift and the amplitude of the principal mode of surface pressure distribution are systematically reported, to provide direct evidence for possible wind wave growth theories. Intermittent and localised airflow separation is observed for steep waves with small wave age, but its effect on setting the phase-averaged pressure distribution is not drastically different from that of non-separated sheltering. We find that the wave form drag force is not a strong function of wave age but closely related to wave steepness. In addition, the history of wind wave coupling can affect the wave form drag, due to the wave crest shape and other complex coupling effects. The normalised wave growth rate we obtain agrees with previous studies. We make an effort to clarify various commonly adopted underlying assumptions, and to reconcile the scattering of the data between different previous theoretical, numerical and experimental results, as we revisit this longstanding problem with new numerical evidence.
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影响因子：
2.9
作者：
Shemer
通讯作者：
Shemer
影响因子：
3.7
作者：
Mostert, W.;Popinet, S.;Deike, L.
通讯作者：
Deike, L.
影响因子：
3.7
作者：
W. Mostert;L. Deike
通讯作者：
L. Deike
影响因子：
3.7
作者：
W. Melville;A. Fedorov
通讯作者：
A. Fedorov
影响因子：
3.7
作者：
Deike, Luc;Popinet, Stephane;Melville, W. Kendall
通讯作者：
Melville, W. Kendall