Experiments on the stability and transition of wind-driven water surfaces
Experiments on the stability and transition of wind-driven water surfaces
复制标题
风动水面稳定性及转变实验
DOI：
10.1017/s0022112001005638
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发表时间：
2001
影响因子：
3.7
通讯作者：
W. Melville
中科院分区：
文献类型：
--
作者：
F. Veron;W. Melville
我们提出的结果，实验室和现场测量的风驱动的水面的稳定性。实验室测量表明，当暴露于从静止开始增加的风时，表面电流和波浪生成伴随着在可比的空间和时间尺度上发生的各种现象。特别感兴趣的是小规模的，流向涡，或朗缪尔环流，环流的增长波场的结构上的明显影响，以及随后的过渡到湍流的表面流的生成。根据梅尔维尔，Shear &贝隆（1998）和贝隆&梅尔维尔（1999 b）最近的工作，我们证明了最初由风产生的波然后被随后的朗缪尔环流强烈调制。调制波变量的直接测量与几何光学和波作用守恒定性一致，但定量比较仍然难以捉摸。在实验参数范围内，根据表面速度和层流剪切层深度，表面波和朗缪尔环流分别在雷诺数为370 ± 10和530 ± 20时首次出现。朗缪尔循环的发生导致在整个表面的热传递的显着增加。在船池中的现场测量显示了在实验室中观察到的相同现象。海气通量的测量，特别是热量和气体传输，和海表温度的影响，进行了讨论。
We present the results of laboratory and field measurements on the stability of wind-driven water surfaces. The laboratory measurements show that when exposed to an increasing wind starting from rest, surface current and wave generation is accompanied by a variety of phenomena that occur over comparable space and time scales. Of particular interest is the generation of small-scale, streamwise vortices, or Langmuir circulations, the clear influence of the circulations on the structure of the growing wave field, and the subsequent transition to turbulence of the surface flow. Following recent work by Melville, Shear & Veron (1998) and Veron & Melville (1999b), we show that the waves that are initially generated by the wind are then strongly modulated by the Langmuir circulations that follow. Direct measurements of the modulated wave variables are qualitatively consistent with geometrical optics and wave action conservation, but quantitative comparison remains elusive. Within the range of parameters of the experiments, both the surface waves and the Langmuir circulations first appear at constant Reynolds numbers of 370 ± 10 and 530 ± 20, respectively, based on the surface velocity and the depth of the laminar shear layer. The onset of the Langmuir circulations leads to a significant increase in the heat transfer across the surface. The field measurements in a boat basin display the same phenomena that are observed in the laboratory. The implications of the measurements for air–sea fluxes, especially heat and gas transfer, and sea-surface temperature, are discussed.