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arXiv · 1901.04269

Subcritical turbulent condensate in rapidly rotating Rayleigh-Bénard convection

Benjamin Favier·Céline Guervilly·Edgar Knobloch
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Abstract

The possibility of subcritical behaviour in the geostrophic turbulence regime of rapidly rotating thermally driven convection is explored. In this regime a non-local inverse energy transfer may compete with the more traditional and local direct cascade. We show that, even for control parameters for which no inverse cascade has previously been observed, a subcritical transition towards a large-scale vortex state can occur when the system is initialized with a vortex dipole of finite amplitude. This new example of bistability in a turbulent flow, which may not be specific to rotating convection, opens up new avenues for studying energy transfer in strongly anisotropic three-dimensional flows.

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Benjamin Favier, Céline Guervilly, Edgar Knobloch. 2019-01-14. Subcritical turbulent condensate in rapidly rotating Rayleigh-Bénard convection. https://doi.org/10.1017/jfm.2019.58

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