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arXiv · chao-dyn/9906015

Spectra and statistics of velocity and temperature fluctuations in turbulent convection

Shay Ashkenazi·Victor Steinberg
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Abstract

Direct measurements of the velocity in turbulent convection of $SF_6$ near its gas-liquid critical point by light scattering on the critical density fluctuations were conducted. The temperature, velocity and cross frequency power spectra in a wide range of the Rayleigh and Prandtl numbers show scaling behaviour with indices, which are rather close to the Bolgiano-Obukhov scaling in the wavenumber domain. The statistics of the velocity fluctuations remains Gaussian up to the Reynolds numbers $10^5$.

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Shay Ashkenazi, Victor Steinberg. 1999-06-09. Spectra and statistics of velocity and temperature fluctuations in turbulent convection. https://doi.org/10.1103/physrevlett.83.4760

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