Exit of a Heterogeneous Detonation Wave into a Channel with Linear Expansion. II. Critical Propagation Condition

Abstract

Propagation of a detonation wave in monodisperse suspensions of reacting particles (based on the model of the suspension of aluminum particles in oxygen) in channels with linear expansion is studied within the framework of mechanics of heterogeneous reacting media. Reduced kinetics is described with allowance for the transitional (from diffusion to kinetic) regime of combustion of micron-sized and submicron-sized spherical aluminum particles. The effects of the channel width, particle diameter, and expansion angle on propagation conditions and detonation regimes are determined. The critical channel width is found to be a nonmonotonic function of the expansion angle, which is associated with qualitatively different wave patterns behind an oblique step. Flow charts are constructed, and the results are compared with solutions of problems of heterogeneous detonation wave propagation in channels with a backward-facing step and with sudden expansion.