A study of the UTSI transaugmented and classical railgun

In the past few years it has been determined that conventional railguns have nearly reached their velocity limits due to ablation of rail and insulator materials. The UTSI transaugmented railgun was constructed to conduct experiments to investigate the potential of augmentation in increasing the force on the plasma armature without increasing armature current. Preliminary experiments were performed to obtain values for the self and mutual inductances of the UTSI railgun which were needed for performance evaluations. The experiments consisted of generating a current pulse on one of the sets of rails and measuring the voltage and current induced on the other set of rails. From the measurements, the inductances were calculated. Classical railgun shots were performed to determine an ablation constant, the force on the projectile due to the pressure from the light gas gun and the vaporization of the fuse. Augmented shots in which the operating current on the inner rail was the same as one of the classical shots were performed. Using the parameters obtained from the unaugmented shots, simulations were performed for the augmented shots. The velocity profiles obtained from experimental data were not in agreement with the predicted values. The experimental increase in velocity due to the augmenting field was approximately half the predicted value.