Pellet injection in the RFP (Reversed Field Pinch)

Conference · Fri Jan 01 00:00:00 EST 1988

OSTI ID:6642649

Wurden, G A; Weber, P G; Munson, C P; Cayton, T E; Bunting, C A; Carolan, P G

Observation of pellets injected into the ZT-40M Reversed Field Pinch has allowed a new twist on the usual tokamak ablation physics modeling. The RFP provides a strong ohmic heating regime with relatively high electron drift parameter (xi/sub drift/ /approximately/ 0.2), in the presence of a highly sheared magnetic field geometry. In situ photos of the pellet ablation cloud using a grated-intensified CCD camera, as well as two-view integrated photos of the pellet trajectory show substantial modification of the original pellet trajectory, in both direction and speed. Depending on the launch geometry, increases in the initial 500 m/s pellet speed by 50% have been observed, and a ski jump deflector plate in the launch port has been used to counteract strong poloidal curvature. In contrast to the tokamak, the D/sub ..cap alpha../ light signature is strongest near the edge, and weaker in the plasma center. Additional information on ion temperature response to pellet injection with 20 ..mu..sec time resolution has been obtained using a 5-channel neutral particle analyzer (NPA). The energy confinement is transiently degraded while the beta is largely unchanged. This may be indicative of pellet injection into a high-beta plasma operating at fixed beta. 10 refs., 6 figs.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6642649
• Report Number(s): LA-UR-88-3831; CONF-8810231-2; ON: DE89003496
• Resource Relation: Conference: IAEA technical committee meeting on pellet injection and toroidal confinement, Gut Ising, F.R. Germany, 24 Oct 1988; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
REVERSE-FIELD PINCH
PELLET INJECTION
ELECTRON DENSITY
JOULE HEATING
PLASMA CONFINEMENT
TRAJECTORIES
CONFINEMENT
ELECTRIC HEATING
HEATING
PINCH EFFECT
PLASMA HEATING
RESISTANCE HEATING
700205* - Fusion Power Plant Technology- Fuel
Heating
& Injection Systems