Gas flow rates through inert and chemically reactive porous beds

Abstract

The Atomic Weapons Establishment is interested in the behaviour of highly reactive chemical beds, in order to produce more reliable explosives. To improve understanding of the reaction evolution and bed mechanics the study group investigated the experiments of Goveas (1997), which involved the reaction of small beds of potassium picrate particles. The study group developed a mechanistic model and used simplified analyses to investigate the reaction behaviour. The mechanistic model that was developed is able to explain the periodic chuffing observed in experiments, but does not rely on particle compaction. Two simplified analyses are undertaken, which support this mechanistic interpretation of the experiments. These simplified analyses calculate the reaction front speed based on a thermal analysis and the evolution of the gas bubble rising through the porous bed. The study group also suggest additional work that will further understanding of this phenomenon.