ALEGRA-HEDP THREE DIMENSIONAL SIMULATIONS OF Z-PINCH RELATED PHYSICS

摘要

The complexity associated with the dynamics of wire arrays from individual wire ablation to wire-wire interaction and finally stagnation have been observed with relatively recent advances in experimental diagnostics. These experimental snapshots illustrate the existence of three-dimensional effects (e.g. wire precursor ablation and stagnation, array mass left behind, current density redistribution, multiple stagnations) that have a significant impact on the total radiation output. A detailed understanding of the magnitude and impact of these perturbations is lacking, especially those perturbations in three-dimensions. Sandia National Laboratories has developed a new multi-physics simulation framework tailored to high energy density physics (HEDP) environments. ALEGRA-HEDP has begun to simulate this environment and has produced the highest fidelity, two-dimensional simulations of wire-array precursor ablation to date. The three-dimensional code capability now provides the ability to solve for the magnetic field and current density distribution associated with both the wire array and the complex current return structure. With this new capability the impact that experimental view-ports (e.g., slots in the current return can and radial spokes) have on the magnetic field surrounding the array can be investigated. Specifically, the impact that the perturbed magnetic field has on an idealized cylindrical liner implosion has been investigated.