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arXiv · 1411.5826

Thermal Boundary Layer Equation for Turbulent Rayleigh-Benard Convection

Olga Shishkina·Susanne Horn·Sebastian Wagner·Emily S. C. Ching
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Abstract

We report a new thermal boundary layer equation for turbulent Rayleigh-Benard convection for Prandtl number Pr>1 that takes into account the effect of turbulent fluctuations. These fluctuations are neglected in existing equations, which are based on steady-state and laminar assumptions. Using this new equation, we derive analytically the mean temperature profiles in two limits: (a) Pr>1, Pr~1 and (b) Pr>>1. These two theoretical predictions are in excellent agreement with the results of our direct numerical simulations for Pr=4.38 (water) and Pr=2547.9 (glycerol) respectively.

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Olga Shishkina, Susanne Horn, Sebastian Wagner, Emily S. C. Ching. 2015-01-15. Thermal Boundary Layer Equation for Turbulent Rayleigh-Benard Convection. https://doi.org/10.1103/physrevlett.114.114302

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