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arXiv · 1010.3823

Third-order Elsässer moments in axisymmetric MHD turbulence

Sebastien Galtier
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Abstract

Incompressible MHD turbulence is investigated under the presence of a uniform magnetic field $\bb0$. Such a situation is described in the correlation space by a divergence relation which expresses the statistical conservation of the Elsässer energy flux through the inertial range. The ansatz is made that the development of anisotropy, observed when $B_0$ is strong enough, implies a foliation of space correlation. A direct consequence is the possibility to derive a vectorial law for third-order Elsässer moments which is parametrized by the intensity of anisotropy. We use the so-called critical balance assumption to fix this parameter and find a unique expression.

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Sebastien Galtier. 2010-10-19. Third-order Elsässer moments in axisymmetric MHD turbulence. https://doi.org/10.1016/j.crhy.2010.11.006

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