Kinetic effects in Alfven and ion-cyclotron-wave propagation: Surface eigenmodes and impurity effects

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:5588860

Li, Wannquan

In a circular cylindrical geometry, the author solves a fourth-order set of differential equations numerically for the perturbed fields E{sub {tau}} and E{sub {perpendicular}}. The model takes into account the equilibrium current, magnetic shear, finite {omega}/{omega}{sub c1} effect, mode conversion effects like finite ion gyroradius and electron inertia, and various dissipative mechanisms such as electron Landau and collisional damping, and minority fundamental and majority second harmonic cyclotron absorption. To illustrate the results, the author plots the perturbed electric fields and the energy absorbed by each species. He first examines cold plasma surface Alfven eigenmodes analytically and numerically in a pure plasma. The motivation for this work is to investigate how to avoid the undesirable edge absorption and introduce the methods for the study of impurity effects. In the two-species plasmas, he considers three special examples: (1) minority oxygen in hydrogen in PRETEXT, (2) minority T or H in deuterium in TFTR. He adopts two models: (i) a radially varying minority charge, or (ii) a radially varying magnetic field to investigate the minority gyroresonance heating. The model (ii) is used to examine these three examples. But the model (i) is only applied to the first one. In model (i), it is found that surface modes can induce the eigenmodes and dissipate substantial energy near the hybrid layer in the interior. Some cases analytically manageable are given an interpretation of why there is large or small energy deposition in this layer. It is shown that this strongly depends on poloidal mode numbers, minority concentrations, and minority charge profiles.

• Research Organization: Texas Univ., Austin, TX (United States)
• OSTI ID: 5588860
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700330* -- Plasma Kinetics
Transport
& Impurities-- (1992-)
700340 -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
ALFVEN WAVES
ANALYTICAL SOLUTION
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CLOSED PLASMA DEVICES
CYCLOTRON FREQUENCY
DIFFERENTIAL EQUATIONS
ELECTRIC FIELDS
ELEMENTS
ENERGY LOSSES
EQUATIONS
HEATING
HYDROGEN
HYDROGEN ISOTOPES
HYDROMAGNETIC WAVES
IMPURITIES
ION PLASMA WAVES
ION WAVES
ISOTOPES
KINETICS
LIGHT NUCLEI
LOSSES
MODE CONVERSION
NONMETALS
NUCLEI
NUMERICAL SOLUTION
ODD-EVEN NUCLEI
OXYGEN
PLASMA HEATING
PLASMA IMPURITIES
PLASMA SIMULATION
PLASMA WAVES
RADIOISOTOPES
SIMULATION
TFTR TOKAMAK
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TRITIUM
WAVE PROPAGATION
YEARS LIVING RADIOISOTOPES