Loss of propulsive force in railguns with laminated containment

The effect of a close-fitting laminated containment structure on propulsive L´ is studied both experimentally and computationally. It is shown that the interaction of axial magnetic fields near the armature with the laminations transfers a fraction of the propulsive force to the containment. This reduces the propulsive L´ without causing significant reduction in the rail L´. The effect is very sensitive to the spacing between armature and containment. The loss of propulsive force may be as large as 20 to 25% for very close spacing