Optimizing Study on the Concave Arc Surfaced C-Shaped Armature With Medium and Small Calibers

Previous studies on solid armatures show that concave-arc-surfaced C-shaped armature (ASCA) can improve the contact pressure and current distribution at the armature/rail interface in a railgun system. However, concrete design or parameter study of the concave ASCA is rarely mentioned. In fact, besides the basic structural parameters for conventional C-shaped armatures, there are two more key structural parameters for the concave ASCA, namely, the radius (r) and the central angle (8) of their surface arc. In this paper, three matching models of the concave armatures contacting with the corresponding rail structures are discussed and compared, and consequently, the best structure pattern of the contact is presented. Meanwhile, the radius and the central angle of the arc in the ASCA are proposed and analyzed. With a fixed railgun caliber and minimum thickness of armature trailing edge, the optimal 8 and r are determined according to the current distribution obtained in simulation. The concave ASCAs for square-caliber railgun of 20, 30, 40, and 50 mm calibers are discussed, and their optimal structural parameters are presented, respectively.