Temperature Spectra in Shear Ow and Thermal Convection
نویسنده
چکیده
We show that the P u (!) / ! ?7=3 shear velocity power spectrum gives rise to a P (!) / ! ?4=3 power spectrum for a passively advected scalar, as measured in experiment high Rayleigh number Rayleigh Benard ow, we can account for the measured scaling exponents equally well as the Bolgiano Obukhov theory (BO59). Yet, of the two explanations , only the shear approach might be able to explain why no classical scaling range is seen in between the shear (or BO59) range and the viscous subrange of the experimental
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