Dispersal Characteristics Dependence on Mass Ratio for Explosively Driven Dry Powder Particle

Abstract

An investigation on the dispersal characteristics of the cylindrically packed material of dry powder particles driven by explosive load is presented. By establishing a controllable experimental system under laboratory conditions and combining with near-field simulation, the particle dispersal process is described. Additionally, Kelvin–Helmholtz instability is observed during the process of jet deceleration dispersal. The characteristic parameters of radially propagated particles are explored under different mass ratio of particle-to-charge (M/C). Results indicate that, when the charge mass remains constant, an increase in M/C leads to a decrease in dispersed jet number, void radius and maximum velocity, wherein the maximum velocity correlates with calculations by the porous Gurney model. The case of the smaller M/C always has a higher outer-boundary radius and area expansion factor. Findings indicate that when particles detach from the jet upon reaching minimum acceleration and entering low-speed far-field stage from high-speed near-field stage, the outer-boundary radius is 30~36 times the initial particles’ body radius under different M/C. In addition, particle concentration distribution over time and distance is qualitatively analyzed by the grayscale image method. This research can be referential for improving the fire-extinguishing capacity of extinguishing bombs and the damage property of fuel air explosive (FAE).

Editorial for the Special Issue “Materials under High Pressure”

“…Materials would exhibit various dispersion characteristics when driven by explosion. Sun et al [ 3 ] presented an investigation on the dispersal characteristics of the cylindrically packed material of dry powder particles driven by explosive load. By establishing a controllable experimental system under laboratory conditions and combining with near-field simulation, the particle dispersal process was described.…”

“…The interaction between explosion products and materials is very quick, and the strain rate could be extremely high. Preformed fragments can deform or even fracture when subjected to contact blasts, which might lead to a reduction of the terminal effect [ 3 , 4 , 5 ]. To solve this problem, Meng et al [ 5 ] analyzed the effect of surface electroplating on the fragment deformation behavior under contact blasts.…”