  Effects of finite ion temperature on plasma flow in the converging-diverging
magnetic field, the magnetic mirror, or equivalently, magnetic nozzle
configuration, are studied using a quasineutral paraxial two-fluid MHD model
with isothermal electrons and warm magnetized ions. The ion acceleration was
studied with an emphasis on the role of the singularity at the sonic point
transition. It is shown that the regularity of the sonic point defines a global
solution describing plasma acceleration from subsonic to supersonic velocity.
Stationary accelerating solutions were obtained and compared with the time
dependent dynamics, confirming that the solutions of the time-dependent
equations converge to the stationary solutions and therefore are stable. The
effects of the ion pressure anisotropy were analyzed using Chew-Goldberger-Low
model and its generalization. It is shown that the mirror force (manifested by
the perpendicular ion pressure) enhances plasma acceleration. The role of
ionization and charge exchange on plasma flow acceleration have been
investigated.
