Modeling of a poloidally symmetric toroidal field divertor in a reversed--field-pinch plasma machine

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

OSTI ID:5313722

Matheson, P L

Magnetic divertors have been shown to be successful in minimizing plasma-wall interactions and in leading to high confinement regimes in Tokamaks. This leads to the hope that similar benefits may occur in an Reversed-Field-Pinch (RPF) fitted with a divertor. Previous experiments using divertors in a RFP have used a poloidal field divertor configuration such as is used in Tokamaks. This study investigates another approach; namely a toroidal field divertor. In this study a simple model of a poloidally symmetric toroidal field divertor is developed and used in a study of stochastic effects due to the divertor and in a 3-D magnetohydrodynamic (MHD) code to study the response of the plasma to the large poloidal m = 0 perturbations caused by the divertor coils. It is found that the topology of the RFP-divertor system is much more complex than had been expected. Stochasticity is enhanced in the outer edge region of the plasma because of this geometrical complexity. The way of the RFP reaches an equilibrium in this complex system is investigated with the 3-D relaxation code, DEBS (authored by Dalton Schnack). This code showed that the divertor will not hinder the formation of a reversed toroidal field in the plasma, and that the dynamics of its formation is altered when toroidal effects are considered. The plasma develops flows and currents in the throat of the divertor in response to the vacuum-like divertor fields. These flows and currents help to restore the force free character of the plasma.

• Research Organization: Brigham Young Univ., Provo, UT (United States)
• OSTI ID: 5313722
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700420* -- Fusion Technology-- Plasma-Facing Components-- (1992-)
CLOSED PLASMA DEVICES
COMPUTER CODES
D CODES
DIVERTORS
FLUID MECHANICS
HYDRODYNAMICS
MAGNETOHYDRODYNAMICS
MATHEMATICAL MODELS
MECHANICS
PINCH DEVICES
PINCH EFFECT
POLOIDAL FIELD DIVERTORS
REVERSE-FIELD PINCH
STOCHASTIC PROCESSES
THERMONUCLEAR DEVICES
THREE-DIMENSIONAL CALCULATIONS
TOKAMAK DEVICES
TOROIDAL FIELD DIVERTORS
TOROIDAL PINCH DEVICES