Vorticity generation by short‐crested wave breaking
Vorticity generation by short‐crested wave breaking
复制标题
短峰波破碎产生涡量
DOI：
10.1029/2012gl054034
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发表时间：
2012
影响因子：
5.2
通讯作者：
B. Raubenheimer
中科院分区：
文献类型：
--
作者：
D. B. Clark;S. Elgar;B. Raubenheimer
与碎波相关的漩涡和漩涡迅速地将污染物、营养物和陆地物质沿着海岸分散。虽然理论和数值模型表明，涡量是在破碎波峰的两端附近产生的，但这一假设尚未在现场得到验证。在这里，我们报告了波浪产生的垂直涡度的第一个观测结果（例如，水平涡），并发现单个短峰破碎波在冲浪带中产生显著的涡度[O（0.01 s−1）]。左手和右手波端产生相反符号的涡度，与理论一致。与理论相反，观察到的涡度也增加内部的破碎波峰，可能是由于岸上平流的涡度产生的前几个阶段的破碎或从破碎区的形状。短峰破碎将能量从入射波转移到低频旋转运动，这是海岸线附近分散的主要机制。
Eddies and vortices associated with breaking waves rapidly disperse pollution, nutrients, and terrestrial material along the coast. Although theory and numerical models suggest that vorticity is generated near the ends of a breaking wave crest, this hypothesis has not been tested in the field. Here we report the first observations of wave‐generated vertical vorticity (e.g., horizontal eddies), and find that individual short‐crested breaking waves generate significant vorticity [O(0.01 s−1)] in the surfzone. Left‐ and right‐handed wave ends generate vorticity of opposite sign, consistent with theory. In contrast to theory, the observed vorticity also increases inside the breaking crest, possibly owing to onshore advection of vorticity generated at previous stages of breaking or from the shape of the breaking region. Short‐crested breaking transferred energy from incident waves to lower frequency rotational motions that are a primary mechanism for dispersion near the shoreline.