Study on tail structural parameters of monolithic C-type armature based on analysis of mechanical pre-contact pressure in non-equal-cross-section cantilever model

It is necessary to maintain adequate contact pressure between rail and armature for avoiding transition in solid armature railgun. At current buildup stage, this contact pressure is often provided by deformation of the solid armatures. In this paper, non-equal-cross-section cantilever model of monolithic C-type armature´s tail was proposed firstly. Then the equation of deflection curve associated with the tail structural parameters was established. Based on the requirements of the mechanical pre-contact pressure, the relationship between structure of armature tail and the deflection curve was established; meanwhile the relationship between the pre-contact pressure and structural parameters of the armature tail was discussed. The results showed that reasonable design of armature tail structural parameters can meet the requirements of mechanical pre-contact pressure at current ramp-up. Based on non-equal-cross-section cantilever model, several kinds of armatures were designed. In certain circumstance, transition is eliminated using this kind of armature in launch experiment with 2500m/s speed.