Wire Dynamics and Ablation Model for the Implosion of Wire Arrays of Complex Geometry and Composition

Abstract

Summary form only given. The wire dynamics model (WDM) can effectively replace the generic 0D model in simulation of implosions of arbitrarily-shaped wire arrays, including low-wire-number nested and planar array loads on 1 MA generators as well as high-wire-number array loads on multi-MA current accelerators. Fast and inexpensive WDM modeling can predict the array implosion time and the rate of thermalization of the kinetic energy, and can estimate the timing of the X-ray pulse . Besides serving the purposes of the design and optimization of the wire array loads of complex configurations, WDM reproduces the specific features of wire array implosion dynamics due to inductive current transfer, such as, for example, the increased stability of the stagnating Z-pinch in nested and planar array configurations. The generic 0D model is known to neglect wire ablation dynamics during the array implosion. However, by introducing additional current filaments associated with currents through the ablated plasmas one can evolve the WDM to the wire ablation dynamics model (WADM). In addition to the WDM, the WADM allows modeling of the dynamics of trailing mass and current in a self-consistent magnetic field of an arbitrarily-shaped array including wire arrays of complex composition, e.g., when the inner and outer arrays of a nested array are built of different wire materials. In the latter case the WADM can take into account effects due to the difference in ablation times for inner and outer arrays. Both the WDM and WADM can be considered as valuable amplifications of MHD models of wire ablation and array implosion.