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arXiv · 1808.08510

Similarity model for corner roll in turbulent Rayleigh-Benard convection

Wen-Feng Zhou·Jun Chen
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Abstract

The corner roll (CR) in the Rayleigh-Bénard (RB) convection accounts for the behaviors of heat transport and convection flow at the corner. Streamlines of the three-dimensional direct numerical simulations for $10^8<Ra<5\times10^9$ show that CR presents well-defined similarity and multi-layer structure. A stream function for CR is developed by homotopy and the structure ensemble dynamics. The model presents the scaling of Reynolds number of corner roll $Re_{cr}\sim Ra^{1/4}$. Scaling of CR scale $r = 0.77 Ra^{-0.085}$ indicates strong near-wall shearing induced by wind and provides a probability of the `ultimate regime' at high $Ra$.

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Wen-Feng Zhou, Jun Chen. 2018-09-02. Similarity model for corner roll in turbulent Rayleigh-Benard convection. https://doi.org/10.1063/1.5054647

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