Thermomechanical Analysis of Plasma-Facing Components for SST-1 Tokamak

Plasma-facing components (PFCs) are an important part of the Indian Steady State Superconducting Tokamak (SST-1) design. The main consideration in the design of PFCs is steady-state heat removal of up to 1 MW/m² , which is nearly the limit for incident heat flux of mechanically attached graphite tiles for tokamak PFCs. SST-1 PFCs consist of divertors, passive stabilizers, baffles, and limiters and are designed for long-pulse operation, which requires active cooling of these components. During steady-state operation, the average heat loads on the divertor and passive stabilizers are expected to be 0.6 and 0.25 MW/m² , respectively. Design considerations include two-dimensional steady-state and transient tile temperature distribution and the resulting thermal loads in PFCs during plasma operation. Thermal analysis is carried out to evaluate the thermomechanical behavior of the SST-1 PFCs. In this technical note, temperature distribution and thermally induced stresses and strains in PFCs are analyzed using a finite element method, and the effect of stress and strain on different materials used in PFCs is discussed.