Abstract

An improved drift approximation model with an added radial electrostatic field has been successfully developed to quantitatively describe the plasma motion in the toroidal solenoid in a FCVA system. It is found that the additional radial electric field mainly confines the z-directional drift of the ions. A perfect quantitative fit is obtained for our simulation results to the Storer’s experimental data. Our model also provides the value of the plasma density and the electron-ion collision frequency as a function of the B field strength and they agree perfectly with the experimental data cited in the literature. The potential difference between the duct wall and the plasma centre which gives the radial electric field can also be determined from the simulation, and the results are in the same order as measured.

© 1995 Optical Society of America