Blast waves generated in an unconfined space by a nonideal detonation of high-density aluminum-enriched formulations

Abstract

Experiments on the detonation of high-density (1.8 g/cm³) aluminum-ammonium perchlorate-paraffin-RDX formulations in an unconfined space demonstrated their high efficiency at pressure amplitudes within 0.3–7.0 atm. The relative pressure amplitude and impulse of the blast waves with respect to the analogous characteristics of TNT charges of the same mass were found to be 1.3–2.4. The TNT equivalents in pressure and impulse vary with the distance nonmonotonically, ranging within 1.4–2.8. The blast wave produced by an infield explosion of a 1.42-kg composite charge demonstrated its high performance characteristics. Measurements at blast wave amplitudes of 1 to 20 atm gave a TNT equivalent in pressure of up to 3 and a TNT equivalent in impulse of 1.3 to 1.8. The high parameters of blast waves in an unconfined space originate from both the high-energy characteristics of the systems themselves and the afterburning of excess metal fuel in air. To estimate the extent of participation of the reaction of excess metal fuel with air in supporting the blast wave, numerical simulations of the generation of blast waves for various rates of mixing of detonation products with air at the contact surface were conducted. The main elements of the mechanisms of the processes that determine the efficiency of explosive systems with a heat release spread in space and time were considered. It was concluded that an optimal regime of blast wave generation, capable of ensuring a prolonged attenuation of the wave with the distance, could be realized for low-velocity detonation.