The effects of air gaps and inert layers on exploding bridgewire detonator function

Abstract

ABSTRACT Exploding bridgewire (EBW) detonators work by electrically exploding a thin conducting wire as a result of a high voltage discharge from a capacitor. The process creates a strong UV (ultraviolet) emission and a shock compaction wave into the surrounding porous explosive bed. To investigate the significance of each, the research presented here utilized air gaps, an optical window, or inert porous powders between the bridge and explosive powder bed. The thickness of the air gap was varied to attenuate the air shock but allow the transmission of UV light. The optical properties of the inert porous bed were varied to allow a similar shock compaction to occur, but with different intensities of UV light. Finally, a thin optical window was used that blocked the shock, but allowed transmission of the UV light. It is clearly shown that both UV light and shock compaction are important to the functioning of EBW detonators at practical energy levels although each is individually capable of resulting in detonation if sufficient pure energy of either form is applied.