학술논문

FRC translation dynamics and plasma confinement properties in FRX-C/T
Document Type
Conference
Author
Source
Conference: Japan/US joint symposium on compact toroid research, Hiroshima, Japan, 13 Nov 1984
Subject
70 PLASMA PHYSICS AND FUSION TECHNOLOGY REVERSE-FIELD PINCH
PLASMA CONFINEMENT
ACCELERATION
COMPACT TORUS
ENERGY LOSSES
SCALING LAWS
CLOSED PLASMA DEVICES
CONFINEMENT
LOSSES
PINCH EFFECT
THERMONUCLEAR DEVICES
TORI 700101* -- Fusion Energy-- Plasma Research-- Confinement, Heating, & Production
Language
English
Abstract
In the FRX-C/T experiment field-reversed configuration plasmas are translated over 16 meters without inducing instabilities or enhanced transport. The plasmas are formed in either a puff or static D/sub 2/ fill and they are accelerated to axial speeds of up to the ion thermal velocity. The observed acceleration dynamics agree with 2-D MHD simulations. When translated into reduced external magnetic fields, FRCs are observed to accelerate, expand, and cool in approximate agreement with adiabatic theory. The plasmas reflect from an external mirror with negligible loss in thermal energy, particle inventory, and poloidal magnetic flux. After each reflection the axial kinetic energy is reduced by approximately 50%. Because of this reduction, FRCs are readily trapped without the need of pulsed gate magnet coils. Translation has also allowed the scaling of FRC confinement over an extended parameter space with plasma dimensions, temperatures, and densities varying by factors of 2 to 4. An empirical scaling law of the observed nonclassical particle confinement shows departures from the lower-hybrid-drift scaling. Particle transport accounts for approximately one-half of the total energy loss. The confinement parameter, n tau/sub E/ approx. = 10/sup 11/ s/cm/sup 3/, is observed with n approx. = 10/sup 15/ cm/sup -3/ and T/sub i/ approx. = 0.6 keV.