Experimental investigation of the natural divertor configuration in Heliotron-E

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

OSTI ID:7247012

Hillis, D L; Mioduszewski, P K; Fowler, R H; Rome, J A; Motojima, O; Mizuuchi, T; Noda, N; Mutoh, T; Zushi, H; Takahashi, R; Obiki, T; Iiyoshi, A; Uo, K

Particle control with pump limiters and divertors has been successfully demonstrated in a number of present-day tokamaks. In a heliotron/stellarator configuration, plasma flows to the wall in distinct flux bundles, often called ''divertor stripes''. This complicated three-dimensional characteristic of the plasma edge presents a new challenge for active particle control systems such as pump limiters and divertors. The experiment described here has obtained data with an instrumented pump particle collector that is located in the ''natural'' magnetic divertor stripe of Heliotron-E. The particle collector consists of a moveable graphite assembly with single-sided particle collection and active pumping. By scanning the particle collector assembly through the plasma edge of Heliotron-E, the divertor stripe is observed to be about 2-3 cm (FWHM) in width, and pressure rises of 0.01-0.01 mTorr are observed in the particle collector pumping chamber. These measurements have demonstrated that particles leaving the bulk plasma via the divertor stripes can be collected and provide a basis for developing a divertor scheme for particle control in helical systems. Modelling of the Heliotron-E magnetic configuration at the plasma edge is used to determine the collection efficiency of the particle collector in the divertor stripes. The modeling is further extended to describe a helical divertor concept. 18 refs., 6 figs.

• Research Organization: Oak Ridge National Lab., TN (USA); Kyoto Univ., Uji (Japan). Plasma Physics Lab.
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 7247012
• Report Number(s): CONF-880512-4; ON: DE88010444
• Resource Relation: Conference: 8. international conference on plasma surface interactions in controlled fusion devices, Julich, F.R. Germany, 2 May 1988
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
HELIOTRON
DIVERTORS
PLASMA CONFINEMENT
EXPERIMENTAL DATA
FIRST WALL
PUMPED LIMITERS
CLOSED PLASMA DEVICES
CONFINEMENT
DATA
INFORMATION
LIMITERS
NUMERICAL DATA
THERMONUCLEAR DEVICES
THERMONUCLEAR REACTOR WALLS
700101* - Fusion Energy- Plasma Research- Confinement
Heating
& Production