Influence of Insulation Support Spacing on Contact State Between Rotating Armature and Rail

The round bore railgun is more conducive to improving the firing accuracy by using the electromagnetic drive projectile rotation launch technology. However, at present, only the influence of the rail and armature structure parameters on the launch performance has been studied, and the influence of the insulation support structure on the launch performance has not been considered. In this article, first, the numerical calculation model of a 15 mm caliber railgun is established. According to the current carrying demand of 300 kA, different armature structure design schemes are obtained by changing the tail length and interference. Second, the insulation support structure is introduced, and the influence of the insulation support spacing on the contact performance is obtained. By changing the angle
$\theta $
of the armature relative to the rail and introducing the relative probable error
$\beta $
to represent the consistency of the rotating contact state, the influence law of the insulation support spacing and the length of the armature tail on the consistency of the rotating contact is obtained. Finally, according to the above theoretical analysis results, two types of railguns with different insulation spacing are built and verified by electromagnetic launch experiments. The results show that the increase of the insulation support spacing is conducive to improving the armature-rail contact performance, but is not conducive to the consistency of the armature rotation contact state. Although increasing the insulation distance will affect the consistency of the contact force between the armature and rail with the rotation angle
$\theta $
, it can greatly improve the contact state in the bore and enhance the electromagnetic launch efficiency.