Improved Formalism for Flowing Two-Fluid Equilibrium and Its Application to ST

Abstract

An improved formalism for flowing two-fluid equilibria with non-uniform density is developed in the limit of no dissipation. The system for axisymmetric equilibria can be expressed using second order differential equations for the stream functions of the generalized vorticities of the electron and ion fluids plus an algebraic equation for the density. These simultaneous equations have six arbitrary functions for the stream functions of poloidal flows, the specific entropies and the generalized enthalpies for the electron and ion fluids. It is found that the type of the equation for the ion generalized vorticity is elliptic (hyperbolic) when the poloidal ion flow speed is less (larger) than the sonic speed. This property is different from the single-fluid model. As significant poloidal ion flow may exist even in the present experiment, this difference is getting important.