Use of a fast shock tube as an injector for electromagnetic railgun

The FST-railgun is a new type of hypervelocity chemical-electromagnetic launcher for use as a high-pressure EOS (equation of state) research tool. To reduce the effect of barrel ablation of railgun and accelerate projectiles to higher velocities, the fast shock tube (FST), a cylindrical convergent HE (high explosive) launcher, is used as the injector of this novel railgun. The FST injector can provide injection velocities of up to 7 to 8 km/s, which results in final muzzle velocities of railgun up to 20 km/s with sufficient energy. The helium gas of the FST injector is partially ionized to plasma by strong shock waves driven by HE and the plasma is used as the armature of a back-stage railgun. This paper describes the configuration of FST-railgun and establishes an internal ballistics model of FST-railgun for analyzing the performance of the FST-railgun and evaluating the feasibility of experiment. The FST can also be used as the injector of electrothermal gun. This FST-electrothermal gun is also briefly introduced.