Universal Return to Isotropy of Inhomogeneous Atmospheric Boundary Layer Turbulence
Universal Return to Isotropy of Inhomogeneous Atmospheric Boundary Layer Turbulence
复制标题
非均匀大气边界层湍流各向同性的普适回归
DOI：
10.1103/physrevlett.126.194501
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发表时间：
2021
影响因子：
8.6
通讯作者：
Calaf, Marc
中科院分区：
文献类型：
--
作者：
Stiperski, Ivana;Katul, Gabriel G.;Calaf, Marc
湍流物理学中的一个顽固问题是，大尺度各向异性涡旋的能量含量随着尺度的减小而重新分布的趋势的表示，这种现象被称为回归各向同性。首次组装了一组史无前例的大气湍流测量数据，覆盖了从平坦到山区的地形，从对流到非常稳定的层结，地表粗糙度超过几个数量级，以及远远超过直接数值模拟和实验室实验极限的雷诺数，并用于探索尺度回归各向同性。一旦考虑了与湍流产生有关的大尺度上的初始各向异性，速度分量之间的能量均分的多条途径被证明是普遍的。
A recalcitrant problem in the physics of turbulence is the representation of the tendency of large-scale anisotropic eddies to redistribute their energy content with decreasing scales, a phenomenon referred to as return to isotropy. An unprecedented dataset of atmospheric turbulence measurements covering flat to mountainous terrain, stratification spanning convective to very stable conditions, surface roughness ranging over several orders of magnitude, and Reynolds numbers that far exceed the limits of direct numerical simulations and laboratory experiments was assembled for the first time and used to explore the scalewise return to isotropy. The multiple routes to energy equipartitioning among velocity components are shown to be universal once the initial anisotropy at large scales, linked to turbulence generation, is accounted for.