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arXiv · 1401.2138

Prediction of temperature distribution in turbulent Rayleigh-Benard convection

Zhen-Su She·Xi Chen·Hong-Yue Zou·Yun Bao·Jun Chen·Fazle Hussain
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Abstract

A quantitative theory is developed for the vertical mean temperature profile (MTP) in turbulent Rayleigh-Benard convection (RBC), which explains the recent experimental and numerical observations of a logarithmic law by Ahlers et al.(Phys. Rev. Lett., 2012). A multi-layer model is formulated and quantified, whose predictions agree with DNS and experimental data for the Rayleigh-number (Ra) over seven decades. In particular, a thermal buffer layer follows a 1/7 scaling like the previously postulated mixing zone (Procaccia et al, Phys. Rev. A,1991), and yields a Ra-dependent log law constant. A new parameterization of Nu(Ra) dependence is proposed, based on the present multi-layer quantification of the bulk MTP.

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Zhen-Su She, Xi Chen, Hong-Yue Zou, Yun Bao, Jun Chen, Fazle Hussain. 2014-01-09. Prediction of temperature distribution in turbulent Rayleigh-Benard convection. https://arxiv.org/abs/1401.2138

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