This paper is concerned with detonation-propelled shocks (precursors) occurring in gas-permeable charges. It is shown that the basic aspects of the event may successfully be reproduced within a one-dimensional two-phase picture widely employed in the modelling of porous energetic materials. Precursor shocks are sustained by intense gasification of the solid phase, provided the ignition pressure (Pign) exceeds a certain critical level. At high enough Pign, the post-shock flow is found to acquire a contact discontinuity. Although this pattern is compatible with the associated self-similar solution, the question of the mechanism governing its formation remains open.
- channel effect
- contact discontinuities in gas flows
- detonation in tubular charges
- gas-permeable explosives
- precursors in two-phase detonation