Dimensional transition in rotating turbulence.
Dimensional transition in rotating turbulence.
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旋转湍流中的维度转变。
DOI：
10.1103/physreve.90.023005
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
S. Musacchio
中科院分区：
文献类型：
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作者：
E. Deusebio;G. Boffetta;E. Lindborg;S. Musacchio
在这项工作中，我们通过直接数值高粘性模拟来研究旋转如何影响湍流的二维化。在“分裂级联”的框架内，我们研究了一层薄薄的流体，在二维强迫下，注入的能量既流向小尺度（产生直接级联）又流向大尺度（形成逆级联）。结果表明，旋转增强了逆叶栅，而削弱了正叶栅，从而促进了流动的二维化。这是通过在大尺度上抑制熵的产生来实现的。尽管如此，我们发现，在研究的旋转速率范围内，增加计算域的垂直尺寸会导致逆级联的通量减少。我们的研究结果表明，即使在旋转气流中，当垂直尺度相对于强迫尺度足够大时，逆叶栅也可能最终消失。我们还研究了分裂级联和约束对旋转引起的对称性破缺的影响。
In this work we investigate, by means of direct numerical hyperviscous simulations, how rotation affects the bidimensionalization of a turbulent flow. We study a thin layer of fluid, forced by a two-dimensional forcing, within the framework of the "split cascade" in which the injected energy flows both to small scales (generating the direct cascade) and to large scale (to form the inverse cascade). It is shown that rotation reinforces the inverse cascade at the expense of the direct one, thus promoting bidimensionalization of the flow. This is achieved by a suppression of the enstrophy production at large scales. Nonetheless, we find that, in the range of rotation rates investigated, increasing the vertical size of the computational domain causes a reduction of the flux of the inverse cascade. Our results suggest that, even in rotating flows, the inverse cascade may eventually disappear when the vertical scale is sufficiently large with respect to the forcing scale. We also study how the split cascade and confinement influence the breaking of symmetry induced by rotation.