The use of currents induced within a conducting shield for railgun performance control

A conducting containment (shield) is an important part of an electromagnetic launcher and can ensure the rigidity of the whole construction. The electromagnetic fields, generated by a flowing current, are dissipated within the shield, with a resultant partial loss of energy. On the other hand the shield varies the inductance gradient and current form in the launcher circuit. The containment currents produce magnetic pressure on the rails' exterior thus compensating the inner pressure. The problem is to neutralize the inner pressure on the rails without any considerable reduction in the inductance gradient. We have used method of numerical experiment for investigating the influence of physical containment characteristics upon the launch process. A three-dimensional model of a round bore railgun with a moving solid armature has been studied. Its construction allows the use of various materials with different qualities. The model predicts the disappearance of total radial force acting on the entire rail when the inductance gradient is reduced by 1.5-2.5 times.