Steady-state magnetohydrodynamic clump turbulence

Journal Article · Wed Mar 01 04:00:00 EST 1989 · Phys Fluids B; (United States)

DOI:https://doi.org/10.1063/1.859167· OSTI ID:6386060

Tetreault, D J

The turbulent steady state of the magnetohydrodynamic (MHD) clump instability (Phys. Fluids 31, 2122 (1988)) is investigated. The steady state is determined by the balance between clump growth by turbulent mixing and clump decay by field line stochasticity. The turbulent fields driving the mixing are generated self-consistently from Ampere's law and conserve the magnetic helicity. In the steady state, the mean current and magnetic field satisfy J/sub 0/ = ..mu..B/sub 0/, where ..mu.. depends on the mean-square fluctuation level. Above this critical point (J/sub 0/>..mu..B/sub 0/), the plasma is MHD clump unstable. MHD clump instability is a dynamical route to the force-free, Taylor state. For the steady state to exist, ..mu.. must exceed a threshold on the order of that required for B/sub 0//sub z/ field reversal. Steady-state MHD clump turbulence corresponds to field reversed Taylor states. From the ..mu.. threshold condition, the steady-state fluctuation spectrum (deltaB/sub rms//B) is calculated and shown to increase with mean driving current as theta/sup 3/, where theta is the pinch parameter.

• Research Organization: Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
• OSTI ID: 6386060
• Journal Information: Phys Fluids B; (United States), Journal Name: Phys Fluids B; (United States) Journal Issue: 3 Vol. 1:3; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
FLUCTUATIONS
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
INSTABILITY GROWTH RATES
MAGNETOHYDRODYNAMICS
MECHANICS
PLASMA
PLASMA INSTABILITY
STEADY-STATE CONDITIONS
STOCHASTIC PROCESSES
TURBULENCE
VARIATIONS