BPX divertor conceptual design and analysis

This paper reports that for its primary mode of operation, the Burning Plasma Experiment (BPX), uses a double-null divertor for the removal of energy and charged particles from the plasma. The power handling performance of the divertor is critical to the achievement of the experimental objectives of BPX. Due to the high-power densities and the use of inertial cooling, high thermal conductivity annealed pyrolytic graphite (PG) and one-dimensional carbon fiber composites are the two leading candidates for the plasma facing material. To maximize the power handling capability of the divertor, a tile thickness (normal to the plasma facing surface) greater than 30 mm, essentially infinitely thick for the burn durations being considered for BPX, is used and the separatrix is swept across the divertor surface to spread the heating over as large an area as possible. In the baseline divertor design concept, an arrangement of 546 modules form a continuous surface, at the top and bottom, around the toroidal circumference of the vacuum vessel