A Compuational Study of Fiber and Wire Array Z-Pinches

Trac-II is a two dimensional axisymmetric resistive magnetohydrodynamic code. It simulates all three spatial components (r,z,φ ) of the magnetic field and fluid velocity vectors, and the plasma is treated as a single fluid with two temperatures (electron and ion). In addition, it can optionally include a self-consistent external circuit. Recent modifications to the code include the addition of the 3-T radiation model, a 4-phase (solid-liquid-vapor-plasma) equation of state model based on the work of Lee and More (QEOS), and a 4-phase electrical/thermal conductivity model. These changes permit the detailed study of fiber and wire array Z-pinches. Specifically, we will study the initiation of a single tungsten wire in 1-d using a PBFA-Z circuit model for the pre-pulse. Then, using these results as initial radial conditions in 2-D we will investigate the dynamics of wire array configurations in the r-θ plane. Special emphasis will be placed on determining the dependence of plasma merge time on initial wire gap and mass.