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arXiv · 1209.6201

Boundary layers in turbulent Rayleigh-Bénard convection in air

Ronald du Puits·Johannes Rilk·Christian Resagk·André Thess
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Abstract

The boundary layer flow in a Rayleigh-Bénard convection cell of rectangular shape has been visualized in this fluid dynamics video. The experiment has been undertaken in air at a Rayleigh number $Ra=1.3\times 10^{10}$ and a Prandtl number $Pr=0.7$. Various sequences captured at selected positions of the heating plate show that the boundary layer is a very transient flow region characterized by coherent structures that permanently evolve. It becomes fully turbulent in the areas where the large-scale circulation impinge or leave the bottom plate.

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Ronald du Puits, Johannes Rilk, Christian Resagk, André Thess. 2012-09-27. Boundary layers in turbulent Rayleigh-Bénard convection in air. https://arxiv.org/abs/1209.6201

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