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arXiv · 0811.0462

Prandtl-, Rayleigh-, and Rossby-number dependence of heat transport in turbulent rotating Rayleigh-Benard convection

Jin-Qiang Zhong·Richard J. A. M. Stevens·Herman J. H. Clercx·Roberto Verzicco·Detlef Lohse·Guenter Ahlers
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Abstract

Experimental and numerical data for the heat transfer as a function of the Rayleigh-, Prandtl-, and Rossby numbers in turbulent rotating Rayleigh-Benard convection are presented. For relatively small $Ra ~ 10^8$ and large Pr modest rotation can enhance the heat transfer by up to 30%. At larger Ra there is less heat-transfer enhancement, and at small Pr = 0.7. there is no heat-transfer enhancement at all. We suggest that the small-Pr behavior is due to the breakdown of the heat-transfer-enhancing Ekman pumping because of larger thermal diffusion.

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Jin-Qiang Zhong, Richard J. A. M. Stevens, Herman J. H. Clercx, Roberto Verzicco, Detlef Lohse, Guenter Ahlers. 2008-11-04. Prandtl-, Rayleigh-, and Rossby-number dependence of heat transport in turbulent rotating Rayleigh-Benard convection. https://doi.org/10.1103/physrevlett.102.044502

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