在三维流中,拉格朗的和欧勒的缩放指数的和和多分数
Dhawal Buaria1,2, Katepalli R Sreenivasan1,3
1Tandon School of Engineering, New York University, New York, New York 11201, USA.
Physical review letters
|December 1, 2023
概括
在流中,拉格朗的和欧勒的缩放指数表现出不同的和行为. 两者都表现出多分形性质,拉格朗日间歇性与横向欧勒尔间歇性联系在一起.
科学领域:
- 流体动力学 流体动力学
- 流理论 流理论
- 统计力学 统计力学
背景情况:
- 了解流需要分析结构函数的缩放指数.
- 同位态流模拟提供了对普遍缩放规律的洞察.
研究的目的:
- 为了研究拉格朗日和欧勒结构函数的惯性范围缩放指数.
- 为了比较拉格朗的和欧勒的动荡的多分质性质.
主要方法:
- 直接数值模拟的同otropic 动荡.
- 在泰勒尺度上的结构函数分析,雷诺兹数高达1300.
主要成果:
- 横向欧勒尔缩放指数在高阶 (p≥10) 中和在~2.1.
- 拉格朗日缩放指数在较高数量级 (p≥8) 中和在2左右.
- 一个共享的多分体光谱通过结假设将拉格朗日和横向欧勒尔指数联系起来.
结论:
- 拉格朗日间歇性似乎以横向欧勒尔间歇性为特征.
- 这些发现表明,在纵向和横向欧勒尔描述之间存在明显的多分形行为.
- 讨论了在散射范围内的多分形预测的含义,特别是对于拉格朗日加速.
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