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arXiv · 1912.05394

Critical transition in fast-rotating turbulence within highly elongated domains

Adrian van Kan·Alexandros Alexakis
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Abstract

We study rapidly rotating turbulent flows in a highly elongated domain using an asymptotic expansion at simultaneously low Rossby number $Ro\ll 1$ and large domain height compared to the energy injection scale, $h=H/\ell_{in}\gg 1$. We solve the resulting equations using an extensive set of direct numerical simulations for different parameter regimes. As the parameter $λ= (h Ro)^{-1}$ is increased beyond a threshold $λ_c$, a transition is observed from a state without an inverse energy cascade to a state with an inverse energy cascade. } For large Reynolds number and large horizontal box size, we provide evidence for criticality of the transition in terms of the large-scale energy dissipation rate.

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Adrian van Kan, Alexandros Alexakis. 2020-05-28. Critical transition in fast-rotating turbulence within highly elongated domains. https://doi.org/10.1017/jfm.2020.443

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