Detailed analysis of the structural consequences of railgun augumentation

The advantage of augmenting a plasma railgun is to provide the same driving force on the projectile as in an unaugmented railgun at a lower plasma arc current, thus producing less erosion and barrel damage. However, there are structural consequences to railgun augmentation which must be overcome before the advantages of lower plasma arc currents can be realized. To investigate these consequences, a bolted V-block supporting structure is considered with two cores; unaugmented (a single pair of conducting rails), and augmented (conducting rails augmented by a second tandem set of conductors). For each core, a two-dimensional dynamic finite element structural analysis is performed. The loadings, applied sequentially, consist of the static bolt preload, the plasma pressure behind the projectile, and the magnetic pressure induced by currents flowing in the rails or augmenting conductors. The magnetic pressure induced by currents flowing in the rails or augmenting conductors. A maximum rail current is found for which the unaugmented railgun can be fired without permanent deformation of the gun bore, thus allowing repeated firings. For the augmented railgun, at the same projectile acceleration, large permanent deformations are shown. 7 refs., 41 figs., 2 tabs.