Railgun barrel design and analysis

Abstract

For various reasons, contemporary barrel designs for railguns have tended to be somewhat bulky. Ultimately, the more demanding missions expected of railguns than their conventional chemical counterparts pose a special technical problem for the railgun designer in his attempt to minimize weight and maximize launch efficiency, both of which are crucial in many applications currently contemplated for railguns. The key to achieving the dual goals of weight minimization and efficiency maximization lies in the efficient control of the coupled transient electromagnetic, thermal and mechanical effects against the constraints of realizable material properties. These effects frequently place converse geometric constraints on the design. In a recent design study undertaken by Westinghouse, a barrel concept based on an oval geometry for the barrel cross section and an electromagnetically and structurally shaped geometry for the rails is identified as having the greatest potential in attaining this dual goal, especially for solid-armature driven railguns. To facilitate future design efforts, a design methology is presented which is based on a wide spectrum of computational tools for analyzing the multifaceted barrel performance. The iterations between the design-and-analysis cycles are a crucial interplay for railgun barrel development.