レールガン動作の駆動電流立ち上がり依存性

抄録

Railguns are facilities to accelerate projectiles up to several km/s by the electromagnetic force due to a driving current. A variety of current waveforms are used for railguns developed in the world This paper describes the dependence of a railgun operation on a rising rate of the driving current. The use of the exploding wire as an opening switch enables to change the rise time of the driving current. A secondary arc is likely to appear and the erosion on a rail surface is more severe when the current with a short rise time is used. According to the non-dimensional railgun plasma simulation, the current with a short rise time heats up the plasma so fast that plenty of particles ablated from the bore surface, which seem to be the cause of the secondary arc, increase rapidly in the early phase of acceleration.