Numerical studies of liners for magnetized target fusion (MTF)

Summary form only given. Magnetized target fusion (MTF) requires the fast compression of hot, dense plasmas by a conducting liner. We have used two-dimensional MHD calculations to study the electromagnetic implosion of metallic liners driven by realistic current waveforms. Parametric studies have indicated that the liner should reach velocities of 3-20 km/s, depending on the magnetic field configuration, and reach convergence ratios (initial radius divided by final radius) of at least 10. These parameters are accessible with large capacitor bank power supplies such as SHIVA or ATLAS, or with magnetic flux compression generators. One issue with the high currents that are required to implode the liner is that Ohmic heating will melt or vaporize the outer part of the liner. Calculations have shown that this is a realistic concern. We are currently addressing questions of liner instability and flux diffusion under MTF conditions. Another issue is that the magnetic fields needed to inhibit thermal losses to the walls will also heat, melt, or vaporize the inner wall surfaces. For initial fields between 5-50 Tesla, the wall heating is significant but does not result in rapid melting. As the implosion evolves, flux compression leads to fields in excess of 100 Tesla.