动力学效应对能量分散率的概率密度函数的动力学效应,以及流中的 entrophy
Toshiyuki Gotoh1,2, Takeshi Watanabe1, Izumi Saito1
1Department of Physical Science and Engineering, Nagoya Institute of Technology, Gokiso, Nagoya 466-8555, Japan.
Physical review letters
|July 7, 2023
概括
动荡的能量消散和的概率密度函数遵循拉伸的马分布. 由于动力学差异,质分布尾比能量消散尾更长.
科学领域:
- 流体动力学 流体动力学
- 统计力学就是统计力学.
- 流的研究研究流.
背景情况:
- 了解流的统计性质对于许多科学和工程应用至关重要.
- 概率密度函数 (PDF) 提供了关键动量分布的见解.
- 之前的研究已经探讨了流统计的各个方面,但对PDF的能量消耗和缩的尾部的全面理解仍然是积极的研究领域.
研究的目的:
- 确定概率密度函数 (PDFs) 对于流中的能量消散率和度的非对称行为.
- 为了在不同的雷诺兹数中比较PDF的能量消散和缩的尾巴行为.
- 调查PDF文件中任何观察到的差异的潜在动力学和动态原因.
主要方法:
- 使用直接数值模拟 (DNS) 来生成高分辨率的流数据.
- 进行了理论分析,以补充模拟结果并提供分析见解.
- 使用统计方法计算和分析了能量消耗率和质的PDF文件.
主要成果:
- 发现能量消散率和度的PDF都在异常遵循拉伸的马分布.
- 两种分布都有相同的拉伸指数,这是由奇点的动态和可能性决定的.
- 关键的是,与能量消散率PDF相比,PDF表现出较长的左和右尾,无论雷诺兹数如何.
结论:
- 这项研究证实,拉伸的马分布准确地描述了能量消散和缩PDF在流中的非对称行为.
- 动力学差异,特别是贡献项的数量,解释了体和能量消耗率的独特尾部长度.
- 拉伸指数由流动动力学和奇点的潜力控制,为这些动荡量提供了统一的特征.
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