Solid-projectile helical coil electromagnetic launcher

Abstract

Helical coil electromagnetic launchers (HCEML’s) can operate at significantly lower currents and higher efficiency in comparison to conventional railgun and induction coilgun launchers. The HCEML’s versatility is due, in part, to its large inductance gradient which is typically 2 to 3 orders of magnitude greater than conventional railguns and can be tailored to practically any value in that range. The University of Missouri-Columbia (MU) has focused on the development of a low current, high efficiency launcher for low to medium velocity applications. To this end, MU has demonstrated a 40 mm bore × 750 mm length HCEML’s to launch ∼500 gram projectiles to 150 m/s operating at 12 to 15 kA peak currents, 400 to 800 V peak voltages, and measured efficiencies as high as 32%. While this particular HCEML used hollow-projectiles, present research efforts at MU are focused on the development of a solid-projectile HCEML. This investigation describes a 40 mm bore × 300 mm length solid-projectile HCEML. The goal of this research is to demonstrate the solid-projectile HCEML concept and to experimentally measure its performance.