A solution to the radiative collapse problem in Z-pinch simulations

Summary form only given. In a recent paper, Velikovich, et al., proposed a model for enhanced energy coupling in a Z-pinch via the incorporation of exterior magnetic field through the Rayleigh-Taylor unstable plasma-vacuum interface. This theory models the pinch plasma as a foam-like medium saturated with toroidal "magnetic bubbles" which convert field energy to plasma thermal energy once the pinch and entrained bubbles converge to the pinch axis. The present work combines the model equations with a 1-D (radially resolved) radiation magneto-hydrodynamic (MHD) code for the pinch implosion. The pinch plasma is treated as a two fluid medium with a volume fraction Cu comprised of magnetic voids and the remaining fraction of plasma gas. The interface formation rate of bubbles is a parameter of the simulation. The bubbles move through the gas according to a drag equation. Energy is transferred to the ions through drag heating because of the difference in velocity and electrons through pdV work. Separate induction equations for the magnetic field in the plasma gas and in the bubbles are included.