Experiments on field reversed configuration (FRC) formation and their compression using liners

Abstract

Summary form only given. Three types of experiments developing FRC formation, injection, and compression are described: field-compression, FRC formation-translation-capture, and FRC formation- translation-capture-compression. All involve the generation of primarily axial guide and mirror magnetic fields with ~2 Tesla peak fields, using ~5 ms rise time discharges into 9 pulsed magnet coils surrounding the liner implosion portion of the device. The field compression and FRC compression experiments use 12 MA, 4.5 MJ Shiva Star capacitor bank axial discharges to drive implosions of 30 cm tall, 10 cm diameter, 1 mm thick Al shells or liners. The FRC capture experiments are a pre-requisite for the destructive FRC compression experiments. All FRC experiments use 3 capacitor discharges into a segmented theta coil surrounding the FRC formation region to establish a bias field, accomplish pre-ionization of deuterium gas, and provide the reverse field main theta discharge (~1 MA) which forms the FRC. This is aided by two cusp field discharges. The guide and mirror fields enable translation of the FRC and its capture in the liner interior region. Diagnostics include pulsed power (current and voltage), magnetic field, field exclusion, laser interferometry, imaging and spectroscopy, radiography, and both activation and time-of-flight neutron detection. Design features and operating parameters are guided by 2D-MHD simulations.