SCALING LAWS AND DIFFUSE LOCALITY OF BALANCED AND IMBALANCED MAGNETOHYDRODYNAMIC TURBULENCE

doi:https://doi.org/10.1088/2041-8205/722/1/L110

Title: SCALING LAWS AND DIFFUSE LOCALITY OF BALANCED AND IMBALANCED MAGNETOHYDRODYNAMIC TURBULENCE

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Abstract

The search of ways to generalize the theory of strong MHD turbulence for the case of non-zero cross-helicity (or energy imbalance) has attracted considerable interest recently. In our earlier publications, we performed three-dimensional numerical simulations and showed that some of the existing models are inconsistent with numerics. In this Letter, we focused our attention on low-imbalance limit and performed new high-resolution simulations. The results strongly suggest that in the limit of small imbalances we smoothly transition to a standard Goldreich-Sridhar balanced model. We also claim that the Perez-Boldyrev model that predicts the same nonlinear timescale for both components due to the so-called dynamic alignment strongly contradicts numerical evidence.

Authors:

Beresnyak, A; Lazarian, A ^[1]

Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States)

Publication Date:: 2010-10-10

OSTI Identifier:: 21452747

Resource Type:: Journal Article

Journal Name:: Astrophysical Journal Letters

Additional Journal Information:: Journal Volume: 722; Journal Issue: 1; Other Information: DOI: 10.1088/2041-8205/722/1/L110; Journal ID: ISSN 2041-8205

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPUTERIZED SIMULATION; HELICITY; LOCALITY; MAGNETOHYDRODYNAMICS; NONLINEAR PROBLEMS; SCALING LAWS; THREE-DIMENSIONAL CALCULATIONS; TURBULENCE; FLUID MECHANICS; HYDRODYNAMICS; MECHANICS; PARTICLE PROPERTIES; SIMULATION

Citation Formats


                    Beresnyak, A, and Lazarian, A. SCALING LAWS AND DIFFUSE LOCALITY OF BALANCED AND IMBALANCED MAGNETOHYDRODYNAMIC TURBULENCE.  United States: N. p., 2010. 
        Web.  doi:10.1088/2041-8205/722/1/L110.

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                    Beresnyak, A, & Lazarian, A. SCALING LAWS AND DIFFUSE LOCALITY OF BALANCED AND IMBALANCED MAGNETOHYDRODYNAMIC TURBULENCE.  United States.  https://doi.org/10.1088/2041-8205/722/1/L110

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                    Beresnyak, A, and Lazarian, A. Sun .  
        "SCALING LAWS AND DIFFUSE LOCALITY OF BALANCED AND IMBALANCED MAGNETOHYDRODYNAMIC TURBULENCE".  United States.  https://doi.org/10.1088/2041-8205/722/1/L110.

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@article{osti_21452747,

  title        = {SCALING LAWS AND DIFFUSE LOCALITY OF BALANCED AND IMBALANCED MAGNETOHYDRODYNAMIC TURBULENCE},

  author       = {Beresnyak, A and Lazarian, A},

  abstractNote = {The search of ways to generalize the theory of strong MHD turbulence for the case of non-zero cross-helicity (or energy imbalance) has attracted considerable interest recently. In our earlier publications, we performed three-dimensional numerical simulations and showed that some of the existing models are inconsistent with numerics. In this Letter, we focused our attention on low-imbalance limit and performed new high-resolution simulations. The results strongly suggest that in the limit of small imbalances we smoothly transition to a standard Goldreich-Sridhar balanced model. We also claim that the Perez-Boldyrev model that predicts the same nonlinear timescale for both components due to the so-called dynamic alignment strongly contradicts numerical evidence.},

  doi          = {10.1088/2041-8205/722/1/L110},

  url          = {https://www.osti.gov/biblio/21452747},
  journal      = {Astrophysical Journal Letters},

  issn         = {2041-8205},

  number       = 1,

  volume       = 722,

  place        = {United States},

  year         = {2010},

  month        = {10}

}

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Journal Article:

https://doi.org/10.1088/2041-8205/722/1/L110

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