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Probability density function of turbulent velocity fluctuations in rough-wall boundary layer

H. Mouri·M. Takaoka·A. Hori·Y. Kawashima
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Abstract

The probability density function of single-point velocity fluctuations in turbulence is studied systematically using Fourier coefficients in the energy-containing range. In ideal turbulence where energy-containing motions are random and independent, the Fourier coefficients tend to Gaussian and independent of each other. Velocity fluctuations accordingly tend to Gaussian. However, if energy-containing motions are intermittent or contaminated with bounded-amplitude motions such as wavy wakes, the Fourier coefficients tend to non-Gaussian and dependent of each other. Velocity fluctuations accordingly tend to non-Gaussian. These situations are found in our experiment of a rough-wall boundary layer.

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H. Mouri, M. Takaoka, A. Hori, Y. Kawashima. 2003-07-23. Probability density function of turbulent velocity fluctuations in rough-wall boundary layer. https://doi.org/10.1103/physreve.68.036311

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