Simulation of Void Collapse in an Energetic Material, Part 2: Reactive Case

In Part 1 a numerical methodology was used to study collapse of voids in energetic materials by ignoring the contributions of the gas phase and chemical reaction. In this paper, the thermomechanical response of solid phase is combined with the vapor-phase compression and chemical reactions to study their effects on the energy deposition mechanisms. The formulation and numerical treatment of the coupled solid-gas interactions, including heat release caused by chemical reactions, are discussed. The effects of loading intensity and void size are studied. The results show that for the micron-size voids under consideration significant gas-phase chemical reactions occur. However, their influence on the void collapse itself is minimal. Results indicate that when voids completely collapse a significant amount of reaction products are created, but the collapse time is too short to set up thermal runaway at the hot spot before void collapse.