Neutral Beam Orientation on the Tokamak Fusion Test Reactor

The efficiency of plasma heating and current drive expected in the Tokamak Fusion Test Reactor has been computed for various orientations of neutral injection beamlines. Computer codes that model plasma transport and particle orbits have been used to compute power losses caused by “shinethrough,” charge-exchange, intersection of particle orbits with the limiter or wall, and toroidal field ripple, and to compute the effect of finite size particle orbits on penetration of injected beam particles. Less readily quantifiable considerations such as impurity contamination and toroidal plasma rotation are discussed briefly.