Joint statistics between temperature and its dissipation rate components in a round jet
Joint statistics between temperature and its dissipation rate components in a round jet
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圆形射流中温度及其耗散率分量的联合统计
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
F. Anselmet
中科院分区：
文献类型：
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作者：
J. Mi;R. Antonia;F. Anselmet
在微热湍流圆形射流的自保区域中研究了温度波动 θ 和温度耗散率 eθ 的所有三个分量之间的联合统计。决定θ和eθ之间相关性的主要因素是p(θ)的不对称性、θ的概率密度函数(PDF)以及小尺度湍流的各向异性。 θ 和 eθ 之间统计独立性的假设在该流动中似乎比在湍流平面射流中更接近。相关地，圆形射流比平面射流更能满足局部各向同性的假设。当 θ 在 ±2 个标准差范围内时，以 θ 为条件的 eθ 所有分量的期望在流动的完全湍流部分中近似相等；条件期望的大小与独立性假设一致。
The joint statistics between the temperature fluctuation θ and all three components of the temperature dissipation rate eθ are investigated in the self‐preserving region of a slightly heated turbulent round jet. The main factors which determine the correlation between θ and eθ are the asymmetry of p(θ), the probability density function (PDF) of θ, and the anisotropy of the small‐scale turbulence. The assumption of statistical independence between θ and eθ appears to be more closely approximated in this flow than in a turbulent plane jet. Relatedly, the assumption of local isotropy is also more closely satisfied in the round jet than in the plane jet. When θ is in the range ±2 standard deviations, the expectations of all components of eθ, conditioned on θ, are approximately equal in the fully turbulent part of the flow; the magnitude of the conditional expectation is consistent with the independence assumption.