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Small scale structures in three-dimensional magnetohydrodynamic turbulence

P. D. Mininni·A. Pouquet·D. C. Montgomery
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Abstract

We investigate using direct numerical simulations with grids up to 1536^3 points, the rate at which small scales develop in a decaying three-dimensional MHD flow both for deterministic and random initial conditions. Parallel current and vorticity sheets form at the same spatial locations, and further destabilize and fold or roll-up after an initial exponential phase. At high Reynolds numbers, a self-similar evolution of the current and vorticity maxima is found, in which they grow as a cubic power of time; the flow then reaches a finite dissipation rate independent of Reynolds number.

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P. D. Mininni, A. Pouquet, D. C. Montgomery. 2006-07-28. Small scale structures in three-dimensional magnetohydrodynamic turbulence. https://doi.org/10.1103/physrevlett.97.244503

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