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arXiv 1912.12866physics.flu-dynnlin.CD
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turbulence中的标度律

Scaling laws in turbulence

Yves Pomeau, Martine Le Berre

摘要:

根据高雷诺数湍流中的耗散是由时空中的奇异事件和无粘欧拉方程的解描述的思想,我们得出结论,在这种流动中,标度律应仅取决于欧拉方程中出现的量。这排除了粘度或湍流长度作为标度参数,并限制了这一限制的彻底可能的分析图片。我们专注于牛顿定律的阻力为一个弹丸在静止的流体中快速移动。受牛顿阻力定律的启发(在大雷诺数极限下与运动物体速度的平方成比例),当确定了边界层的分离位置时,这在实验中得到了很好的验证,我们提出了湍流尾流中雷诺应力与速度场相关量之间的显式关系(在时间上平均,但取决于空间),在一个积分微分方程的形式为速度,解决了一个Poietille流在一个圆形管道。

英文摘要:

Following the idea that dissipation in turbulence at high Reynolds number is by events singular in space-time and described by solutions of the inviscid Euler equations, we draw the conclusion that in such flows scaling laws should depend only on quantities appearing in the Euler equations. This excludes viscosity or a turbulent length as scaling parameters and constrains drastically possible analytical pictures of this limit. We focus on the law of drag by Newton for a projectile moving quickly in a fluid at rest. Inspired by the Newton's drag force law (proportional to the square of the speed of the moving object in the limit of large Reynolds numbers), which is well verified in experiments when the location of the detachment of the boundary layer is defined, we propose an explicit relationship between Reynolds's stress in the turbulent wake and quantities depending on the velocity field (averaged in time but depending on space), in the form of an integro-differential equation for the velocity which is solved for a Poiseuille flow in a circular pipe.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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