Numerical techniques in electromagnetic compatibility-oriented design of rail launchers operating with plasma armatures

In this paper the electromagnetic interferences radiated from a railgun operating with plasma armatures are studied. The level of emission during the initial explosion of the fuse barrel that forms successively the metallic arc is computed by integrating numerically Maxwell's equations in complete form via a suitable numerical code, written in C++ programming language, and based on a three-dimensional finite difference algorithm in the space and in the time domain. The electric and magnetic field during the acceleration of the plasma armature, successive to its formation, are evaluated by means of a quasi-stationary model based on the assumed transient current distribution in the rails and the armature and on a given relation between the current and the position of the armature. The results indicate that both methods can be considered useful tools in the analysis of the electromagnetic environment around rail launchers.