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

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.

6 pages, to appear in Physical Review E

References in corpus (2)

• Probability density function of turbulent velocity fluctuation
• Distributions of Fourier Modes of Cosmological Density Fields

Cited by in corpus (10)

• Interstellar Turbulence I: Observations and Processes
• Contrasts Between Momentum and Scalar Transport Over Very Rough Surfaces
• Large-scale lognormal fluctuations in turbulence velocity fields
• On Landau's prediction for large-scale fluctuation of turbulence energy dissipation
• Vortex Tubes in Turbulence Velocity Fields at Reynolds Numbers 300-1300
• Unlikely existence of $k_x^{-1}$ spectral law in wall turbulence: an observation of the atmospheric surface layer
• Statistical mechanics and large-scale velocity fluctuations of turbulence
• Dependence of the asymptotic energy dissipation on third-order velocity scaling
• Logarithmic scaling for fluctuations of a scalar concentration in wall turbulence
• Mathematical model for logarithmic scaling of velocity fluctuations in wall turbulence