Inertial Range Scaling, Kármán-Howarth Theorem and Intermittency for Forced and Decaying Lagrangian Averaged MHD in 2D
نویسندگان
چکیده
We present an extension of the Kármám-Howarth theorem to the Lagrangian averaged magnetohydrodynamic (LAMHD−α) equations. The scaling laws resulting as a corollary of this theorem are studied in numerical simulations, as well as the scaling of the longitudinal structure function exponents indicative of intermittency. Numerical simulations are presented both for freely decaying and for forced two dimensional MHD turbulence, solving directly the MHD equations, and employing the LAMHD−α equations at 1/2 and 1/4 resolution. Linear scaling of the third-order structure function with length is observed. The LAMHD−α equations also capture the anomalous scaling of the longitudinal structure function exponents up to order 8.
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