Acceleration of solid particles by gaseous detonation products

Abstract

This investigation is concerned with a theoretical and experimental study of acceleration dynamics of spherically inert solid particles (100 μm nominal diameter) in flows of gaseous detonation products. The experiments were conducted in a detonation channel 1.5 m long with a 20 × 20 mm 2 cross section and one open end. Particle motion was observed with the method of multiexposure photographic recording and a laser stroboscopic light source. The character of velocity variation of individual particles inside and outside of the channel was investigated for different initial positions of particles. Under certain conditions the accelerated particles are destroyed. A mathematical model based on two-phase multivelocity continuum mechanics has been formulated to describe the detonation wave propagation, outflow of detonation products from the chanel, and interaction between particles and a nonstationary flow of detonation products. The model includes chemical equilibrium of detonation products. particle acceleration, heat exchange between phases and channel walls, particle melting, and fragmentation of droplets if the Weber number exceeds some critical value. Particle destruction has been correlated with the initial position, diameter, and physical properties of particles. Comparison of computer and experimental results shows that the model satisfactorily describes acceleration, heating, and fragmentation of particles.