Augmented Electromagnetic Accelerators—Technical Solutions and New Ideas

Electromagnetic accelerators enable the acceleration of bodies in the gram to kilogram range to velocities above 2 km/s. The Lorentz force is responsible for the acceleration; it is proportional to the electric current in the body's armature and the magnetic field produced by the electric current in the rails. Typically, a large electric current is necessary to create the accelerating force in accelerator configurations with one pair of rails. The large electric currents, which can reach several mega-amperes and the friction forces between the armature and the rails leading to wear the area of the contact. This causes a transition from solid contact to plasma contact increasing the wear of the material. To delay the transition, which limits the performance and the lifetime of the electromagnetic accelerator, the current through the armature has to be decreased. This can be realized by applying an external magnetic field, which augments the magnetic field between the rails and compensates for the reduced current in the armature. In the past, different techniques in the field of augmented electromagnetic accelerators were investigated. This paper gives an overview of augmentation techniques investigated so far. Furthermore, the concept of a modular augmented staged electromagnetic launcher (MASEL) is introduced. This MASEL is being implemented in a new accelerator for the experimental investigations.