Non-Gaussian probability distribution functions in two-dimensional magnetohydrodynamic turbulence
Dipartimento di Fisica, Università degli Studi della Calabria
87036 Rende (CS), Italy and INFM, Unità di Cosenza, Italy
2 Laboratoire G. D. Cassini, CNRS UMR 6529, OCA Observatoire de Nice B.P. 4229, 06304 Nice Cedex 04, France
Accepted: 30 June 2000
Intermittency in MHD turbulence has been analyzed using high-resolution 2D numerical simulations. We show that the Probability Distribution Functions (PDFs) of the fluctuations of the Elsässer fields, magnetic field and velocity field depend on the scale at hand, that is they are self-affine. The departure of the PDFs from a Gaussian function can be described through the scaling behavior of a single parameter obtained by fitting the PDFs with a given curve stemming from the analysis of a multiplicative model by Castaing et al. (Physica D, 46 (1990) 177). The scaling behavior of the parameter can be used to extract information about the intermittency. A comparison of intermittency properties in different MHD turbulent flows is also performed.
PACS: 47.27.Jv – High-Reynolds-number turbulence / 47.27.Gs – Isotropic turbulence; homogeneous turbulence / 47.65+a – Magnetohydrodynamics and electrodynamics
© EDP Sciences, 2000