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arXiv · 1711.06005

Logarithmic scaling for fluctuations of a scalar concentration in wall turbulence

H. Mouri·T. Morinaga·T. Yagi·K. Mori
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Abstract

Within wall turbulence, there is a sublayer where the mean velocity and the variance of velocity fluctuations vary logarithmically with the height from the wall. This logarithmic scaling is also known for the mean concentration of a passive scalar. By using heat as such a scalar in a laboratory experiment of a turbulent boundary layer, the existence of the logarithmic scaling is shown here for the variance of fluctuations of the scalar concentration. It is reproduced by a model of energy-containing eddies that are attached to the wall.

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H. Mouri, T. Morinaga, T. Yagi, K. Mori. 2017-11-16. Logarithmic scaling for fluctuations of a scalar concentration in wall turbulence. https://doi.org/10.1103/physreve.96.063101

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