FINITE-ELEMENT MODELING OF MAGNET COMPRESSION USING COUPLED ELECTROMAGNETIC-STRUCTURAL CODES

A link between the Electromagnetic code, MEGA, and the structural code , DYNA3D has been developed. Although the primary use of this is for m odelling of Railgun components, it has recently been applied to a smal l experimental Coilgun at Bath. The performance of Coilguns is very de pendent on projectile material conductivity, and so high purity alumin ium was investigated. However, due to its low strength, it is crushed significantly by magnetic compression in the gun. Although impractical as a real projectile material, this provides useful benchmark experim ental data on high strain rate plastic deformation caused by magnetic forces. This setup is equivalent to a large scale version of the class ic jumping ring experiment, where the ring jumps with an acceleration of 40kG.