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arXiv · 1311.4598

Heat flux scaling in turbulent Rayleigh-Bénard convection with an imposed longitudinal wind

Andrea Scagliarini·Armann Gylfason·Federico Toschi
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Abstract

We present a numerical study of Rayleigh-Bénard convection disturbed by a longitudinal wind. Our results show that under the action of the wind, the vertical heat flux through the cell initially decreases, due to the mechanism of plumes-sweeping, and then increases again when turbulent forced convection dominates over the buoyancy. As a result, the Nusselt number is a non-monotonic function of the shear Reynolds number. We provide a simple model that captures with good accuracy all the dynamical regimes observed. We expect that our findings can lead the way to a more fundamental understanding of the of the complex interplay between mean-wind and plumes ejection in the Rayleigh-Bénard phenomenology.

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Andrea Scagliarini, Armann Gylfason, Federico Toschi. 2013-11-19. Heat flux scaling in turbulent Rayleigh-Bénard convection with an imposed longitudinal wind. https://doi.org/10.1103/physreve.89.043012

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