Boundary asymmetries and plasma flow to the ALT-II toroidal belt pump limiter
The ALT-II toroidal belt pump limiter has been constructed with 8 radially adjustable limiter blade segments located 45 below the outboard horizontal midplane of TEXTOR. Probe measurements in the shadow of ALT-II are used to detect an asymmetry in the structure of the scrape-off layer above and below the belt limiter. More plasma is incident on neutraliser plates with flux tubes connecting to the outboard side of TEXTOR where the particle flux scrape-off lengths are longer. Neutraliser plates with flux tubes connecting to the bottom/inside of the tokamak receive 10-50% less flux due to a decrease in the characteristic decay lengths. This effect is partially compensated by an ion flow asymmetry favouring the ion drift direction.
Bibliographic Reference: Article: Journal of Nuclear Materials, Vol. 162-164 (1989) pp. 221-225
Record Number: 199010405 / Last updated on: 1994-12-01
Original language: en
Available languages: en