Investigation of liquid gun propellants - Electrical ignition of LGP 1846.

Progress achieved in the study of the electrical ignition of the hydroxylammonium nitrate (HAN)-based liquid gun propellant LPG 1846 is described. The goal of the work is to develop an igniter system suitable for regenerative liquid propellant guns. Several igniter configurations of the one- as well as the two-stage types designed by the Ballistic Research Laboratory and the Frauenhofer-Institut EMI-AFB, have been tested. Voltage and current as well as the pressure histories were recorded. Calculations of electrostatic field distributions discussed here were obtained by a finite element code implemented at Dynamit Nobel. The theoretical analysis yielded alternative electrode designs for future testing. In addition, a specially designed igniter chamber equipped with sapphire windows was used at EMI-AFB to study the fundamentals of the electrical discharge by means of high-speed photography.