DIVERTOR DESIGN FOR THE TOKAMAK PHYSICS EXPERIMENT

In this paper we discuss the divertor design for the planned TPX tokamak, which will explore the physics and technology of steady state (1000 s pulses) heat and particle removal in high confinement (up to 4 x L-mode), high beta (up to beta(N) = 5) divertor plasmas sustained by non-inductive current drive. TPX will operate in the double-null divertor configuration, with actively cooled graphite targets forming a deep (0.57 m) slot at the outer strike point. The peak heat flux on the highly tilted (74 degrees from normal) re-entrant divertor plate (tilted to recycle ions back toward the separatrix) will be in the range of 4-6 MW/m(2) with 17.5 MW of auxiliary heating power. The combination of pumping and gas puffing (D-2 plus impurities), along with higher heating power (45 MW maximum) will allow testing of radiative divertor concepts at ITER-like power densities.