Axisymmetric two-fluid plasma equilibria with momentum sources and sinks

Abstract

Axisymmetric plasma equilibria with toroidal flow are investigated using a two-fluid analysis, taking into account the presence of momentum and current drive, together with dissipative effects. The equilibria are described by a set of three equations describing the spatial variation of poloidal magnetic flux, plasma pressure and toroidal magnetic field. These equations indicate that magnetic flux surfaces do not in general rotate as rigid bodies, as required by ideal magnetohydrodynamics in the absence of momentum sources and poloidal flows. For specific momentum drive and damping scenarios, expressions are obtained giving the variation of density on flux surfaces and the dependence of toroidal rotation rate on temperature that can in principle be tested experimentally. A simple relationship between the loop voltage and plasma current in an inductive tokamak plasma with toroidal flow is also derived.