Turbulence time scales in mixing box experiments
Turbulence time scales in mixing box experiments
复制标题
混合箱实验中的湍流时间尺度
DOI：
10.1007/s00348-002-0536-2
复制
发表时间：
2002
影响因子：
2.4
通讯作者：
B. Sutherland
中科院分区：
文献类型：
--
作者：
K. Dohan;B. Sutherland
摘要。利用不同深度和固定高纵横比水平横截面的水槽，对均匀流体中振荡网格产生的湍流中的涡动时间尺度进行了实验研究。对于高的深度与宽度之比，平均环流以一对反向旋转涡的形式发展。在一种新技术中，珠光染料被用来测量涡流时间尺度，并确定其幂律尺度依赖于与振荡网格的距离。观察到两种标度状态，一种在湍流源附近，另一种在中等深度。在中等深度，如果总流体深度较大，结垢指数会增加。讨论了这些结果对在海洋上层混合层中应用壁面结垢规律的意义。
Abstract. Laboratory experiments are performed to examine eddy time scales in turbulence generated by an oscillating grid in homogeneous fluid using tanks with varying depth and fixed high aspect ratio horizontal cross-section. For high ratios of depth to width, a mean circulation develops in the form of a pair of counter-rotating vortices. In a new technique, pearlescent dye is employed to measure eddy time scales and to determine their power law scaling dependence on the distance from the oscillating grid. Two scaling regimes are observed, one near the source of turbulence and one at intermediate depths. At intermediate depths, the scaling exponent is found to increase if the total fluid depth is larger. We discuss the significance of these results on the use of the law-of-the-wall scaling in the upper oceanic mixed layer.