Beta scaling of transport in microturbulence simulations

Journal Article · Fri Jul 15 00:00:00 EDT 2005 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.1954123· OSTI ID:20764383

Candy, J ^[1]

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1. General Atomics, San Diego, California 92121 (United States)

A systematic study of the beta ({beta}) scaling and spatial structure of thermal and particle transport in gyrokinetic turbulence simulations is presented. Here, {beta} is the ratio of the plasma kinetic pressure to the magnetic pressure. Results show that the nonlinear self-consistent temperature profiles exhibit a (statistically) time-stationary flattening in the vicinity of rational surfaces with a concomitant drop in the electrostatic components of the thermal diffusivity. Simultaneously, the increased magnetic fluctuation amplitude at these surfaces enhances the steady-state electromagnetic (flutter) component of the electron thermal diffusivity. The electromagnetic components of the ion transport coefficients remain close to zero, as expected on theoretical grounds. Only a weak dependence of ion energy transport on {beta} is observed, consistent with recent tokamak experiments [C. C. Petty et al., Phys. Plasmas 11, 2514 (2004)].

• OSTI ID: 20764383
• Journal Information: Physics of Plasmas, Vol. 12, Issue 7; Other Information: DOI: 10.1063/1.1954123; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
AMPLITUDES
CHARGED-PARTICLE TRANSPORT
ELECTRON TEMPERATURE
ELECTRONS
FLUCTUATIONS
ION TEMPERATURE
IONS
MODE RATIONAL SURFACES
NONLINEAR PROBLEMS
PLASMA
PLASMA PRESSURE
PLASMA SIMULATION
SCALING LAWS
STEADY-STATE CONDITIONS
SURFACES
THERMAL DIFFUSIVITY
TOKAMAK DEVICES
TURBULENCE