Rapid Alignment of Velocity and Magnetic Field in Magnetohydrodynamic Turbulence

Journal Article · Fri Feb 29 00:00:00 EST 2008 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.100.085003· OSTI ID:21024813

Matthaeus, W H; Breech, B ^[1]; Pouquet, A ^[2]; Mininni, P D ^[2]; Dmitruk, P ^[1]

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1. Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 18716 (United States)
2. NCAR, P.O. Box 3000, Boulder, Colorado 80307-3000 (United States)

We show that local directional alignment of the velocity and magnetic field fluctuations occurs rapidly in magnetohydrodynamics for a variety of parameters and is seen both in direct numerical simulations and in solar wind data. The phenomenon is due to an alignment between magnetic field and gradients of either pressure or kinetic energy, and is similar to alignment of velocity and vorticity in Navier-Stokes turbulence. This rapid and robust relaxation process leads to a local weakening of nonlinear terms.

• OSTI ID: 21024813
• Journal Information: Physical Review Letters, Vol. 100, Issue 8; Other Information: DOI: 10.1103/PhysRevLett.100.085003; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
KINETIC ENERGY
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
NAVIER-STOKES EQUATIONS
NONLINEAR PROBLEMS
RELAXATION
SIMULATION
SOLAR WIND
TURBULENCE
VELOCITY