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arXiv · 0901.2016

Transitions between turbulent states in rotating Rayleigh-Benard convection

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

Weakly-rotating turbulent Rayleigh-Benard convection was studied experimentally and numerically. With increasing rotation and large enough Rayleigh number an abrupt transition from a turbulent state with nearly rotation-independent heat transport to another turbulent state with enhanced heat transfer is observed at a critical inverse Rossby number $1/Ro_c \simeq 0.4$. Whereas for $1/Ro < 1/Ro_c$ the strength of the large-scale convection-roll is either enhanced or essentially unmodified depending on parameters, its strength is increasingly diminished beyond $1/Ro_c$ where it competes with Ekman vortices that cause vertical fluid transport and thus heat-transfer enhancement.

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Richard J. A. M. Stevens, Jin-Qiang Zhong, Herman J. H. Clercx, Guenter Ahlers, Detlef Lohse. 2009-01-14. Transitions between turbulent states in rotating Rayleigh-Benard convection. https://doi.org/10.1103/physrevlett.103.024503

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