Comparison of Inductance Gradient and Electromagnetic Force in Two Types of Railguns With Two Projectiles by Finite-Element Method

Nowadays lunching masses to faraway distances is an important issue. One of important electromagnetic launcher for this purpose is duble-projectil railgun because it can launch synchronously two separated projectiles. It has been obtained before that two-turn railgun have better inductance gradient and performance than simple railgun. Also, self-inductance gradient and mutual-inductance gradient in two-turn railgun depend on the initial position of armatures. In this paper, we want to calculate the inductance gradient of a new structure that we named it plus railgun. The plus railgun has one barrel between two-pair rails by two separated armatures and two pairs of rails are powered by one pulse power at the same time. A 3-D finite-element method is applied to the transient analysis of the magnetic field, current distribution, and the inductance gradient of railguns. Finally, we will compare the parameters of two-turn and plus railguns.