Flow Measurements in the Edge Region of the RFX-Mod Experiment

In this contribution a detailed study of the edge flow properties performed on the outer region of the RFX-mod experiment using a Gundestrup probe is presented. In particular, both parallel and perpendicular components (with respect to the magnetic field) have been evaluated in several low current discharges providing a complete reconstruction of the edge flow profiles. Different methods based on both magnetized and unmagnetized models have been used to evaluate the averaged plasma flow components and their time variations. Furthermore, configurations involving either ion saturation current signals or floating potential ones have been used to evaluate both parallel and perpendicular flow components and a good agreement has been found between different methods. Finally, the dynamic behaviour of edge flow fluctuations induced by gradient modifications following pellet injection and by varying the edge magnetic topology (the m = 0 islands radial position) have been studied. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.