A deflagration analysis of porous energetic materials with two-phase flow and a multiphase sequential reaction mechanism

A theoretical analysis for the unconfined deflagration of a porous energetic material is developed for a two-step global reaction mechanism that consists of the condensed-phase combustion of the reactive material to produce gas-phase intermediates, followed by a gas-phase reaction that produces final gas-phase products. An asymptotic approach is employed, leading to explicit formulas for the deflagration velocity in specific parameter regimes. The results clearly indicate the influences of two-phase flow and the multiphase, multi-step chemistry on the burning rate, and serve to further characterize the combustion behavior of a significant class of degraded nitramine-type propellants for which the present analysis is applicable.