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arXiv · 1607.01360

Classes of hydrodynamic and magnetohydrodynamic turbulent decay

Axel Brandenburg·Tina Kahniashvili
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Abstract

We perform numerical simulations of decaying hydrodynamic and magnetohydrodynamic turbulence. We classify our time-dependent solutions by their evolutionary tracks in parametric plots between instantaneous scaling exponents. We find distinct classes of solutions evolving along specific trajectories toward points on a line of self-similar solutions. These trajectories are determined by the underlying physics governing individual cases, while the infrared slope of the initial conditions plays only a limited role. In the helical case, even for a scale-invariant initial spectrum (inversely proportional to wavenumber k), the solution evolves along the same trajectory as for a Batchelor spectrum (proportional to k^4.

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Axel Brandenburg, Tina Kahniashvili. 2017-02-04. Classes of hydrodynamic and magnetohydrodynamic turbulent decay. https://doi.org/10.1103/physrevlett.118.055102

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