Abstract

Exploding Foil Initiators for Insensitive Munitions use energy stored in a High Voltage capacitor to produce a high velocity flyer that impacts on the explosive to initiate detonation. To better understand the EFI circuit and predict the resulting flyer velocity the effects of the stored energy and current profile on the EFI have been investigated using circuit modelling and a bespoke analytical mathematical model.
The calculated velocity has been compared with velocity measurements at the end of the EFI barrel using a simple laser based time of arrival experiment. The mathematical model has also been used to help explore the possibility of producing a variable effect by controlling flyer velocity.