Electromagnetic and thermal analysis of muzzle-fed railguns

The electrothermal behaviour of the muzzle-fed railgun configuration, proposed as remedy for the reduction of the velocity skin effect and its related losses in performance, is analysed in this paper by means of a suitable equivalent network approach, that is able to evaluate the distributions of the current density and the temperature in the conductive parts of the railgun. The use of magnetic field augmentation, both in self- and in external-augmented configuration, is proposed, to avoid too low values of the resulting accelerating action, and the dependence of the intensity of the augmentation on the geometrical factor is shown. Finally the possible effects in the reduction of the temperature rise located in the trailing edge zone, responsible for the transition of the armature from solid state to plasma arc are discussed by the analysis of the numerical simulation of shots presented.<>