Small-scale turbulent dynamo

M. Chertkov; G. Falkovich; I. Kolokolov; M. Vergassola

doi:10.1103/physrevlett.83.4065

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arXiv · chao-dyn/9906030

Small-scale turbulent dynamo

M. Chertkov·G. Falkovich·I. Kolokolov·M. Vergassola

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Abstract

Kinematic dynamo theory is presented here for turbulent conductive fluids. We describe how inhomogeneous magnetic fluctuations are generated below the viscous scale of turbulence where the spatial smoothness of the velocity permits a systematic analysis of the Lagrangian path dynamics. We find analytically the moments and multi-point correlation functions of the magnetic field at small yet finite magnetic diffusivity. We show that the field is concentrated in long narrow strips and describe anomalous scalings and angular singularities of the multi-point correlation functions which are manifestations of field's intermittency. The growth rate of the magnetic field in a typical realization is found to be half the difference of two Lyapunov exponents of the same sign.

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M. Chertkov, G. Falkovich, I. Kolokolov, M. Vergassola. 1999-06-17. Small-scale turbulent dynamo. https://doi.org/10.1103/physrevlett.83.4065

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