The toroidal belt pump limiter, ALT-II, in the TEXTOR tokamak
A toroidal belt pump limiter has been installed in the TEXTOR tokamak. The Advanced Limiter TEST-II (ALT-II) is designed to withstand the high heat fluxes intrinsic to the boundary region of tokamak plasmas while simultaneously removing 5% to 10% of the core plasma efflux. The belt consists of eight segments, each 28 cm wide, 150 cm long, and 1.2 cm thick, each covered with shaped graphite tiles. Mounted behind each blade is a "scoop" system which captures plasma flowing past the leading edges and behind the blades. This plasma neutralises on a collector plate and the resulting neutral gas is pumped. During ohmic discharges, 50 to 60 A of current is collected in the scoops and removal rates up to 0.25 Torr l/s are achieved. The blades are instrumented with Langmuir probes and thermocouples, and other diagnostics include infrared cameras, H(alpha)-monitors, pressure gauges, helium charge exchange spectroscopy and helium gas diagnostics. The plasma edge and the operation of the pump limiter system are described.
Bibliographic Reference: Article: Fusion Engineering and Design, Vol. 13 (1990) No. 3, pp. 251-259
Record Number: 199110262 / Last updated on: 1994-12-02
Original language: en
Available languages: en