Fluctuations, turbulence and transports in the presence of drift waves

Technical Report · Fri Feb 01 04:00:00 EST 1980

DOI:https://doi.org/10.2172/5702250· OSTI ID:5702250

Okuda, H; Sato, T; Hasegawa, A; Pellat, R

Turbulence spectrum and plasma diffusion have been studied by theoretical analysis as well as by numerical simulations using a drift wave model in which electrons are assumed to follow the Boltzmann distribution, while ions are assumed to move two-dimensionally in the plane perpendicular to the magnetic field. For a plasma near local thermal equilibrium, it is found that while the ion density diffusion is negligibly small, the energy diffusion is much larger and is comparable to the test particle diffusion. In the presence of strong turbulence, deltan approx. n/sub 0/, fluctuation energy is found to cascade toward long wavelength modes which accompanies the density diffusion. The resultant turbulence spectrum is isotropic in two dimensions perpendicular to the magnetic field. However, the particle diffusion coefficient remains small. When the ion density gradient is maintained by freezing the electron background density, it is found that the turbulence spectrum cascades toward smaller wavenumbers only in the direction perpendicular to the density gradient. As a result an anisotropic turbulence spectrum if formed indicating an appearance of zonal flow in this direction.

• Research Organization: Princeton Univ., NJ (USA). Plasma Physics Lab.
• DOE Contract Number: EY-76-C-02-3073
• OSTI ID: 5702250
• Report Number(s): PPPL-1634
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700105* -- Fusion Energy-- Plasma Research-- Plasma Kinetics-Theoretical-- (-1987)
BOLTZMANN STATISTICS
ELECTRON DENSITY
EQUILIBRIUM
ION DENSITY
ION DRIFT
LTE
MAGNETIC FIELDS
PLASMA DRIFT
PLASMA SIMULATION
PLASMA WAVES
TURBULENCE