Transverse structure of turbulence in a rotating gravity current
Transverse structure of turbulence in a rotating gravity current
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旋转重力流中湍流的横向结构
DOI：
10.1029/2007gl029521
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发表时间：
2007
影响因子：
5.2
通讯作者：
H. Prandke
中科院分区：
文献类型：
--
作者：
L. Umlauf;L. Arneborg;H. Burchard;V. Fiekas;H. Lass;V. Mohrholz;H. Prandke
本文介绍了一个快速（高达0.7 m s - 1）的海洋盐水重力流的湍流动能耗散、流速和水柱分层的天气性、高分辨率测量结果。我们的数据首次提供了重力流内部湍流结构的详细二维图像。强烈的边界层和界面湍流可以与安静的地核区分开来，并且在重力流外缘附近明显存在强烈的不对称混合。这种不对称性反映在计算出的携射速度上，在重力流中大约以5倍的速度变化。本文认为，这种不对称是由于旋转效应造成的，旋转效应在速度场和密度场中也可以清楚地识别出来。
Synoptic, high‐resolution, measurements of turbulent kinetic energy dissipation, current velocity and water column stratification across a fast (up to 0.7 m s−1) oceanic saline gravity current are presented. Our data provide, for the first time, a detailed two‐dimensional picture of the turbulence structure inside a gravity current. Strong boundary‐layer and interfacial turbulence can be distinguished from a quiet core, and a strong asymmetry of mixing near the outer edges of the gravity current is apparent. This asymmetry is mirrored by the computed entrainment velocities, varying approximately by a factor of 5 across the gravity current. It is argued that the asymmetry is due to rotational effects that can be clearly identified also in the velocity and density fields.