The thermal shields for the ITER magnet system: thermal, structural and assembly aspects

The thermal shield system is a continuous barrier between the magnet system operating at 4.5 K and the warm tokamak components. It provides a substantial reduction of both total and local thermal loads to the cold structures to achieve the limits required for normal operation of the superconducting magnet system and maximum heat load of the cryogenic plant. This paper describes details of the design of the different types of thermal shield and presents some results of thermal–hydraulic and structural analyses and some aspects of the assembly procedure for the vacuum vessel thermal shield, which is a challenging task considering the rather small dimensional tolerances that have to be obtained on the fully assembled shield.