Krafter och Stelkroppsroerelser i ett Elektromagnetiski Pansar (Forces and Rigid Motions in an Electromagnetic Armour).

摘要

This report is a theoretical study of the potential of a type of electromagnetic armor designed as an armor against long rod projectiles. The armor consists of two electrically conducting plates connected to a powerful capacitor bank. When the projectile penetrates the two plates it short circuits the capacitor bank and a strong electric current will float through it. This current gives rise to several different global and localized effects on the projectile. In this report we will study the electromagnetic forces acting on the projectile and the mechanical rigid body motions appearing as a result of these forces. The calculations indicate that extremely strong currents are needed in order to produce the forces needed to disturb a full-scale projectile. Currents of several megaamperes must be reached before the perturbations get big enough to seriously affect the penetration. The capacitor banks needed to deliver the required currents will be very large, of the order of tens of megajoules. Capacitor banks that large are not impossible to design but the inevitable become very voluminous when using technology available today. The conclusion is that the type of electromagnetic armor under investigation is not feasible today. Future developments in pulsed power technology might however change this situation. Localized effects (e.g. melting of thin layers, vaporization and magnetohydrodynamic instabilities) could make the protective qualities of the studied electromagnetic armor greater than accounted for here.