Simulation Study on Exploding Foil Initiator

摘要

Simulated investigation of the behavior of exploding foil initiator (EFI) including the electrical explosion of the thin foil and the flyer motion is presented. The technique for the simulation of foil explosion is base on calculations of non-linear resistance, volume expansion and temperature in the five phases i.e. heating of solid-state, melting, fusing, intrinsic exploding and plasma which were divided according to the foil physical state change in the exploding process. The power-time curve derived from the foil simulation was used in one-dimensional hydrodynamic code for simulating the flyer motion. Taking copper as an example, the calculated results coincide well with experimental data and those done by two-dimensional model. After taking into account the energy conversion of the foil explosion, the deviations between the simulated and LLNL experimental data for the flyer velocities lie in ±8%. The simulated curves of the flyer velocity histories coincide well with those of VISAR measurement. So our theoretical technique is more convenient and simpler for describing the design performance of EFI. And this technique also lays a foundation for optimizing EFI.