MINIMUM SIZE Q=1 AND IGNITED SPHERICAL TOKAMAK DEVICES

Abstract

The authors find minimum sized Spherical Tokamak (ST) configurations capable of Q{approximately}1 (scientific break-even) and ignition. For Q{approximately}1 cases, the authors normalize their models to the JET device. They find comparable plasma power balance performance in an ST configuration of major radius {approximately}0.7 m, using both global and 3/2 D plasma transport modeling. For ignited plasma, they first normalize the plasma modeling to the ITER device. They find similar ignited plasma performance capabilities in an ST configuration of major radius 1.2 m. These are much smaller size plasmas than the standard tokamak counterparts, indicating a potentially easier path towards commercial applications. Also, they find that the quantity IA is not a good figure-of-merit for comparing performance of widely different tokamak configurations.