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Sub-Gaussian behavior of the Townsend-Perry constants in turbulent boundary layers
1CNLS and Department of Mathematics, University of California Santa Barbara, California 93106, USA.
Abstract:
A theory is developed to explain the sub-Gaussian behavior of the Townsend-Perry constants (A_{p}) recently measured for high-order fluctuation moments in turbulent boundary layers. It yields the generalized logarithmic law for high-order moments and A_{p}/A_{1}=(ℓ^{*})^{ζ_{p}/p-ζ_{1}}C_{p}^{1/p}/C_{1}, where ζ_{p} are the Kolmogorov-Obukhov-She-Leveque scaling characterizing intermittence effects; ℓ^{*}=1/225 is the only free parameter describing a specific ratio between inertial and energy-containing eddy sizes; C_{p} are raw moments of a Gaussian with unity mean and variance. The predicted A_{p}/A_{1} are in good agreement with experimental data.
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