Numerical modeling of nested wire arrays on the Z accelerator

Summary form only given. The Magnetohydrodynamic (MHD) Rayleigh-Taylor (RT) instability is believed to be one of the limiting factors in z-pinch performance. More specifically, for high velocity, large diameter implosions characteristic of the Z accelerator, numerical calculations suggests that this instability broadens the plasma shell and can account for experimentally measured pulsewidths greater than 6 ns. To improve pinch performance, uniform fills, tailored density profiles, tuning layers (i.e., inner load downstream of outer load), and B/sub z/ stabilization have been proposed to mitigate the RT growth. In all of these schemes, a trade-off exists between improved stability and decreased energy coupling with the machine. The simplest of these techniques to implement and optimize experimentally is the tuning layer. Numerical simulations are presented for a series of nested wire array experiments which were based on the concept of the tuning layer.