Importance of Gas Spaces in the Propagation of Detonation of Granular Explosives

Abstract

IT has been suggested that in low- and medium-velocity detonation in condensed explosives, propagation may be due to heating in the shock front of gas entrapped in the explosive¹. The temperature in these gas pockets has been shown to be very high², and the hypothesis is confirmed by the known effect of increase in gas pressure in stopping detonation in certain granular explosives¹. The temperature attained in the gas depends on the compression ratio and the ratio of the specific heats of the gas, γ. If the hypothesis is correct, increase of γ should cause an increased temperature, and hence an increased rate of reaction, which should be manifested as an increase in the velocity of detonation of the explosive fired at cartridge diameters below that required for maximum velocity. We have now demonstrated this effect experimentally.