Progress in Turbulence VI
Progress in Turbulence VI
复制标题
湍流 VI 的进展
DOI：
10.1007/978-3-319-29130-7_9
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Buxton O
中科院分区：
文献类型：
--
作者：
Buxton O
湍流中大尺度和小尺度波动之间的相互作用不仅具有很大的根本意义，而且对这些相互作用的理解对于大涡模拟（LES）中的亚网格尺度（SGS）应力建模至关重要。在湍流平面混合层的自相似区域，同时获得了两种不同空间分辨率的粒子图像测速（PIV）数据。SGS活动被观察到被放大的并发大规模的低动量波动和衰减的高动量波动的符号和幅度的大规模波动的意义。此外，区域中的大规模的雷诺应力张量的方向是垂直对齐的流动的平均剪切的方向被示出，导致小规模的活动水平的增加。
The interaction between large- and small-scale fluctuations in turbulent flow is not only of great fundamental interest but an understanding of these interactions is fundamental to the modelling of the sub-grid scale (SGS) stresses in a large eddy simulation (LES). Particle image velocimetry (PIV) data is acquired with two different spatial resolutions, simultaneously, in the self-similar region of a turbulent planar mixing layer. The SGS activity is observed to be amplified by concurrent large-scale low momentum fluctuations and attenuated by high momentum fluctuations with both the sign and magnitude of the large-scale fluctuations being of significance. Further, regions in which the orientation of the large-scale Reynolds stress tensor is aligned perpendicularly to the direction of the mean shear of the flow are shown to lead to an increased level of small-scale activity.