Shock interaction with solid particles in condensed matter and related momentum transfer

Abstract

Detonation propagation in a condensed explosive with metal particles can result in significant momentum transfer between the explosive and the particles during their crossing of the leading shock front. Consequently, the assumption of a ‘phaseinteraction–frozen shock’ used in multiphase continuum models for detonation initiation and propagation may not be valid. This paper addresses this issue by performing numerical and theoretical calculations in liquid explosives and RDX with various compressible metal particles under conditions of detonation pressure. The results show that the momentum transferred to heavy–metal particles such as tungsten is not significant after the shock–particle interaction. However, light–metal particles including aluminium, beryllium and magnesium rapidly accelerate during the shockparticle interaction. They reach a considerable speed immediately behind the shock front, typically 60–100% of the flow speed of the explosive. It is important to take this significant momentum transfer at the shock front into account when modelling the shock initiation and detonation structure for two–phase mixtures of condensed explosive and light–metal particles.