Particle description of the interaction between wave packets and point vortices
Particle description of the interaction between wave packets and point vortices
复制标题
波包与点涡相互作用的粒子描述
DOI：
10.1017/jfm.2021.661
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发表时间：
2021
影响因子：
3.7
通讯作者：
R. Salmon
中科院分区：
文献类型：
--
作者：
N. Pizzo;R. Salmon
摘要本文探讨了一种理想化的海洋表面模型，在该模型中，相距很远的表面波包和点涡在两个水平维度上相互作用。我们开始与拉格朗日，在其一般形式，取决于波的作用，波相，流函数和两个额外的字段，标签和跟踪涡的垂直分量的字段。通过假设波作用和涡量被限制在无限小的，广泛分离的区域的流动，我们得到的模型方程是类似的，但显着更一般的，熟悉的系统只包括点涡。我们分析稳定和不稳定的谐波解决方案，解决方案中的波包最终符合点涡（违反我们的假设），和解决方案中的波矢量最终炸毁。此外，我们表明，一个波包诱导净漂移的被动涡在波传播的方向，这是相当于达尔文漂移。推广我们的分析，许多波包和涡，我们研究波包的影响，否则不稳定的涡街和分析显示，根据线性稳定性分析，波包诱导漂移可以稳定的涡街。然后，该系统的数值积分很长一段时间，并示出了一个例子，其中的配置保持稳定，这可能是特别相关的上层海洋。
Abstract This paper explores an idealized model of the ocean surface in which widely separated surface-wave packets and point vortices interact in two horizontal dimensions. We start with a Lagrangian which, in its general form, depends on the fields of wave action, wave phase, stream function and two additional fields that label and track the vertical component of vorticity. By assuming that the wave action and vorticity are confined to infinitesimally small, widely separated regions of the flow, we obtain model equations that are analogous to, but significantly more general than, the familiar system consisting solely of point vortices. We analyse stable and unstable harmonic solutions, solutions in which wave packets eventually coincide with point vortices (violating our assumptions), and solutions in which the wave vector eventually blows up. Additionally, we show that a wave packet induces a net drift on a passive vortex in the direction of wave propagation which is equivalent to Darwin drift. Generalizing our analysis to many wave packets and vortices, we examine the influence of wave packets on an otherwise unstable vortex street and show analytically, according to linear stability analysis, that the wave-packet-induced drift can stabilize the vortex street. The system is then numerically integrated for long times and an example is shown in which the configuration remains stable, which may be particularly relevant for the upper ocean.
影响因子：
3.5
作者：
Leonel Romero;L. Lenain;W. Melville
通讯作者：
Leonel Romero;L. Lenain;W. Melville