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Updated: May 18, 2026

Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Ultimate regime of high Rayleigh number convection in a porous medium
Duncan R Hewitt1, Jerome A Neufeld, John R Lister
1Institute of Theoretical Geophysics, DAMTP, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA, United Kingdom.
Abstract:
Well-resolved direct numerical simulations of 2D Rayleigh-Bénard convection in a porous medium are presented for Rayleigh numbers Ra≤4×10(4) which reveal that, contrary to previous indications, the linear classical scaling for the Nusselt number, Nu~Ra, is attained asymptotically. The flow dynamics are analyzed, and the interior of the vigorously convecting system is shown to be increasingly well described as Ra→∞ by a simple columnar "heat-exchanger" model with a single horizontal wave number k and a linear background temperature field. The numerical results are approximately fitted by k~Ra(0.4).
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