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The Eulerian space-time correlation of strong Magnetohydrodynamic (MHD) turbulence in strongly magnetized plasmas is investigated by means of direct numerical simulations of Reduced MHD turbulence and phenomenological modeling. Two new important results follow from the simulations: 1) counter-propagating Alfvenic fluctuations at a each scale decorrelate in time at the same rate in both balanced and imbalanced turbulence; and 2) the scaling with wavenumber of the decorrelation rate is consistent with pure hydrodynamic sweeping of small-scale structures by the fluctuating velocity of the energy-containing scales. An explanation of the simulation results is proposed in the context of a recent phenomenological MHD model introduced by Bourouaine and Perez 2019 (BP19) when restricted to the strong turbulence regime. The model predicts that the two-time power spectrum exhibits an universal, self-similar behavior that is solely determined by the probability distribution function of random velocities in the energy-containing range. Understanding the scale-dependent temporal evolution of the space-time turbulence correlation as well as its associated universal properties is essential in the analysis and interpretation of spacecraft observations, such as the recently launched Parker Solar Probe (PSP).
We develop a framework for studying the statistical properties of current sheets in numerical simulations of 3D magnetohydrodynamic (MHD) turbulence. We describe an algorithm that identifies current sheets in a simulation snapshot and then determines
In an earlier paper (Wan et al. 2012), the authors showed that a similarity solution for anisotropic incompressible 3D magnetohydrodynamic (MHD) turbulence, in the presence of a uniform mean magnetic field $vB_0$, exists if the ratio of parallel to p
The nanoflare paradigm of coronal heating has proven extremely promising for explaining the presence of hot, multi-million degree loops in the solar corona. In this paradigm, localized heating events supply enough energy to heat the solar atmosphere
A dynamical approach, rather than the usual statistical approach, is taken to explore the physical mechanisms underlying the nonlinear transfer of energy, the damping of the turbulent fluctuations, and the development of coherent structures in kineti
Shell models of hydrodynamic turbulence originated in the seventies. Their main aim was to describe the statistics of homogeneous and isotropic turbulence in spectral space, using a simple set of ordinary differential equations. In the eighties, shel