Reconstruction of the toroidal flow profile of a field-reversed configuration plasma

Abstract

Strong toroidal flow is spontaneously generated in a field-reversed configuration (FRC) plasma. It is continuously accelerated during and after the formation phase. The centrifugal force resulting from the toroidal flow causes deformation of the toroidal cross section, with toroidal mode number n = 2. The radial profile of this selfgenerated toroidal flow has previously been described as rigid rotor (RR) in form, i.e., showing uniform angular velocity. However, the toroidal flow profile observed in these experiments indicates the existence of flow shear. In this work, reconstruction of such a profile, utilizing a modified Abel inversion technique, has been performed, and the resulting detailed toroidal flow profile, including time evolution, has been investigated. © 2012 The Japan Society of Plasma Science and Nuclear Fusion Research.