A New Wall Conditioning Technique Developed on the HT-7 Superconducting Tokamak with a Permanent Magnetic Field

Abstract

4 n e w technique for wall conditioning with a permanent magnetic field has been tested and developed on t h e HT-7 superconducting tokamak by ion cyclotron range frequency wave injection. T h e operation ranges for conditioning and recycling was investigated with different working gas ( 0 2 , He), toroidal field (0.1-2.5 T) and r f powers. T h e experimental results show that its cleaning efficiency is about three times higher than that o f glow discharge cleaning. This n e w technique has been used daily during experiments.

Oxidation for deposits removal and hydrogen release on HT-7

“…The liner is heated by direct current flow and the limiters are heated by thermal radiation. RF wall conditioning techniques have been developed with a permanent toroidal magnetic field [19,20]. Temperatures in the limiter tiles and on the liner were measured by thermocouples.…”