MULTIMEGAJOULE ELECTROMAGNETIC IMPLOSION OF SHAPED SOLID-DENSITY LINERS

Electromagnetic implosions of shaped cylindrical aluminum liners that remain at solid density are discussed. The approximate liner parameter s have an initial radius of 3 to 4 cm, are 4 cm in height, and are app roximately 0.1 cm thick. The liners are driven by the Shiva Star 1300- muf capacitor bank at an 84-kV charging voltage and an approximately 3 0-nH total initial inductance (including implosion load). The discharg e current travels along the length of the liner and rises to 14 MA in approximately 8 mus. The implosion time is approximately 12 mus. Diagn ostics include inductive current and capacitive voltage probes, magnet ic probes, and radiography. Both right-circular cylinder and conical l iner implosion data are displayed and discussed. Radiography indicates implosion behavior substantially consistent with two-dimensional magn etohydrodynamic calculations, which predict inner surface implosion ve locities exceeding 20 km/s, and compressed density of two to three tim es solid density. Less growth of perturbations is evident for the coni cal liner (approximately 1% thickness tolerance) than for the right-ci rcular cylindrical liner (approximately 3% thickness tolerance).