Introduction Electromagnetic Launchers Essay

1006 WordsJan 4, 20135 Pages
Introduction Electromagnetic Launchers Evolving the human fascination of throwing things over great distances, electromagnetic launchers (EMLs) provide the next step in projectile technology. With two different functional designs that utilize magnetic and/or electric fields, both presently more effective (regarding achievable projectile velocities) than conventional combustion-driven firearms. The two effective methods for linearly accelerating a particle deal primarily with maximizing the potential of the Lorentz force, and the force of attraction between two objects with magnetic fields. First, the Lorentz force is the driving force in the technological development of rail guns. In a conceptually counter-intuitive fashion, magnetic fields oriented orthogonal to current carrying wires, instigates an acceleration of the conducting bar that spans the two rails, as show in in the diagram below: The way this force operates is by the cross-product relation of Current and Magnetic field, following the relationship: F=(current)*(length)x(B-field). This force ensures that the bar will continue to be accelerated as long as current is passing through the bar from one rail to the other, adding energy along the entire path of the ‘barrel’. This design improves on traditional firearms, which only have an initial acceleration of the expanding gunpowder to propel the projectile. The alternate design that creates this same result is the coil-gun method. This system utilizes a linear arrangement of one or more concentric coils that draw a projectile ferromagnetic material towards the coil. If more than one coil is used, poly-phase sequencing of the coils must be established, so once the projectile has passed through a coil, it must shut off to not pull the projectile backwards, decelerating it along its path. A simplistic example of the set up is shown below: The