An Investigation of r.f. Travelling Wave Current Drive Using the Model

Abstract

Previous experimental investigations into the use of travelling r.f. waves to drive steady toroidal currents in a toroidal plasma have shown that It, the amount of current driven, is strongly dependent on the ratio of the static toroidal magnetic field Bz, to the strength of the r.f. magnetic field BO). This dependence is characterised by an initial increase and subsequent decrease of It when Btl BfIJ increases. It is shown that this observed behaviour is entirely consistent with the behaviour predicted by the <i X B) current drive model. Results from .numerical computations using the <i X B) model show good quantitative agreement with the published experimental results.