FLUCTUATION-INDUCED TRANSPORT AND POLOIDAL ROTATION IN THE INTERCHANGEABLE MODULE STELLARATOR

Probe measurements over the two-dimensional plasma cross section of th e average and fluctuating density, electron temperature, and potential , as well as the Reynolds stress, have, been made in the Interchangeab le Module Stellarator (IMS) [D. T. Anderson, J. A. Derr, and J. L. Sho het, IEEE Trans. Plasma Sci. PS-9, 212 (1981)]. These measurements wer e performed at two magnetic field strengths, and also when a positivel y biased electrode induces a poloidal plasma flow. The data shows the fluctuation-induced transport to be poloidally asymmetric and dependen t upon the location of the electron cyclotron resonance position, and upon the electrode biasing. The induced poloidal plasma flow changes t he nominally outward fluctuation-induced particle transport to be inwa rd (negative radial transport) by changing the phase relationship of t he density and potential oscillations. The amplitude of the density an d potential fluctuations are, in general, not reduced by the sheared p oloidal flow. Calculations are presented comparing the computed Reynol ds stress induced poloidal plasma flows with the flow calculated from momentum balance.