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arXiv · 1512.07355

Intermittency of Energy Dissipation in Alfvenic Turbulence

Vladimir Zhdankin·Stanislav Boldyrev·Christopher H. K. Chen
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Abstract

We investigate the intermittency of energy dissipation in Alfvenic turbulence by considering the statistics of the coarse-grained energy dissipation rate, using direct measurements from numerical simulations of magnetohydrodynamic turbulence and surrogate measurements from the solar wind. We compare the results to the predictions of the log-normal and log-Poisson random cascade models. We find that, to a very good approximation, the log-normal model describes the probability density function for the energy dissipation over a broad range of scales, but does not accurately describe the scaling exponents of the moments. The log-Poisson model better describes the scaling exponents of the moments, while the comparison with the probability density function is not straightforward.

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Vladimir Zhdankin, Stanislav Boldyrev, Christopher H. K. Chen. 2015-12-23. Intermittency of Energy Dissipation in Alfvenic Turbulence. https://doi.org/10.1093/mnrasl%2Fslv208

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