DESIGN OF AN INDEPENDENT WATER COOLED PLASMA FACING ARMOR WITH MECHANICALLY ATTACHED CONDUCTION COOLED TILES FOR NET FIRST WALL

The “low” temperature (< 1000°C) Plasma Facing Component concept which is under development for NET, is an independent structure located on the plasma facing side of the shielding box. The armor consists of carbon based square tiles, mechanically attached by a spring system, to individual water cooled support plates. A compliant conductive layer to enhance heat transfer from the tile to the cooled structure is foreseen. Assemblies of the dipersoid strengthened copper (glidcop) back plates are brazed to two adjacent poloidally directed stainless steel tubes. The main design specifications are : average surface heat flux : 0.6 MW/m2, volumetric nuclear heating = 7 MW/m3, coolant inlet temperature lower than 100°C and nuclear irradiation of the components of the order of 0.2 dpa. In this paper we report 2D and 3D thermohydraulic and global stress analysis of the structure, the optimization of the compliant layer with the elastic attachment mechanism, the component design compatible with in-situ remote maintenance. The manufacture of the first mock-up for heat flux testing is also described.