Surface Profiles for ALT-II Tiles

摘要

The Advanced Limiter Test-II, ALT-II, is a full toroidal belt limiter that will be installed on TEXTOR in September 1986. The experiment will investigate the effects of a full toroidal belt on particle confinement and on particle exhaust from the system. ALT-II is designed to operate with up to 6 MW of plasma heating for three second discharges. For design purposes it is assumed that as much as 4 MW is deposited on the limiters. In this report the design conditions are coupled with a detailed description of the tokamak plasma edge region to determine the shapes of the graphite tiles that will be mounted on the ALT-II blades. The front faces of these tiles, that surface adjacent to the plasma boundary, are profiled poloidally so that when the energy scrape-off length, lambdae, is 1.0cm the active surfaces experience a heat flux of 270 W/cm sup 2 . The ALT-II belt consists of eight individually movable blades with a 12.0cm gap, for diagnostic access, between adjacent blades. Power flow through these gaps produces hot spots on the toroidal ends of each blade. Heat flux loads associated with these hot spots are minimized by providing toroidal shaping to the end tiles in addition to the poloidal, front face profiling described above. The profiling is such that a single blade protruding 3mm further into the plasma than the next nearest blade experiences 1 kW/cm sup 2 on its toroidal edge during full power operation. (ERA citation 11:042347)