Propagation of detonation waves in gas suspensions in channels with a backward-facing step

Propagation of heterogeneous detonation in a mixture of oxygen and fine aluminum particles in a plane channel with a backward-facing step is studied numerically. The plane detonation regime is taken as the initial flow in the narrow part of the channel. Possible scenarios of evolution of this flow after its passage to the expanded part of the channel are analyzed. The effect of the particle size and channel geometry on detonation propagation/failure is found. Cellular detonation is formed in the wide part of the channel, with a subsequent change in the cell size in the course of establishment of a steady propagation regime. The cell size in steady regimes is invariant with respect to the flow formation process.     

Damping of plane waves generated in an explosion medium during realization of undercompressed detonation modes

Moscow. Translated from Fizika Goreniya i Vzryva, Vol. 25, No. 3, pp. 102–108, May–June, 1989.     

Structure and initiation of plane detonation waves in a bidisperse gas suspension of aluminum particles

Initiation and propagation of plane waves of heterogeneous detonation in a stoichiometric suspension of two fractions of aluminum particles in oxygen are analyzed numerically. It is found that the detonation is not ideal, and the steady-state part of the shock-wave structure is bounded by an equilibrium frozen sonic point. Initiation criteria depend on the particle-size distribution of the mixture. Initiation by explosive shock waves can lead to formation of unstable two-front structures. Addition of a small amount of fine particles into the discrete phase allows the initiation energy to be substantially reduced. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 46–55, March–April, 2008.     

Structure of detonation waves in PETN

A VISAR technique was used to study the structure of the reaction zone in PETN for various initial densities and dispersion of samples. The flow in the pressed charges corresponds to the classical denotation model. In the case of bulk density, the peculiarities corresponding to an explosive combustion model are recorded. In the vicinity of the initial density of 1.7 g/cm³, a kink is found on the curve showing detonation velocity versus density, and the shock-wave initiation of PETN above and below the kink point is studied.