Spectra of the very large anisotropic scales in turbulent channels
Spectra of the very large anisotropic scales in turbulent channels
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DOI：
10.1063/1.1570830
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发表时间：
2003-06-01
影响因子：
4.6
通讯作者：
Jiménez, J
中科院分区：
文献类型：
--
作者：
del Alamo, JC;Jiménez, J
描述和分析了在非常大的盒子中的Re-τ = 180和Re-τ = 550的数值模拟通道的谱。它们支持一种模型，在该模型中，u结构可以分解为两个组件.第一个是由尺寸λ（x）大于或接近5 h，λ（z）接近2 h的结构形成的，其跨越大部分沟道高度，并穿透到缓冲层中。第二个在近壁区域具有最大强度，在那里它是高度各向异性的并且在内部单位中缩放。它变宽，变长，并且在外层变得更加各向同性，在那里它与h成比例。共谱具有类似的准各向同性范围，其宽度随壁距线性增长.在目前的雷诺数下，由于有限的尺度分离，关于可能的流向相似性还不能说什么。从ftp：//torroja可以下载大量的模拟统计数据。干河upm。es/ channels. (C)2003年，美国物理学会。
The spectra of numerically simulated channels at Re-tau = 180 and Re-tau = 550 in very large boxes are described and analyzed. They support a model in which the u- structures can be decomposed in two components. The first one is formed by structures of size lambda(x) greater than or similar to 5 h, lambda(z) approximate to 2 h, which span most of the channel height, and penetrate into the buffer layer. The second one has maximum intensity in the near- wall region, where it is highly anisotropic and scales in inner units. It widens, lengthens, and becomes more isotropic in the outer layer, where it scales with h. The cospectrum exhibits an analogous quasi- isotropic range, whose width grows linearly with wall distance. At the present Reynolds numbers, nothing can be said about a possible streamwise similarity, due to limited scale separation. An extensive set of statistics from the simulations is downloadable from ftp:// torroja. dmt. upm. es/ channels. (C) 2003 American Institute of Physics.