Implications of Mesoscale Phenomena on Modelling the Shock to Detonation Transition at Continuum Scale

摘要

At mesoscale in heterogeneous explosives, reaction proceeds by burning from individual hotspots, whereas at continuum level the reactive burn model needs to represent the integrated effect of burning from many hotspots. Recent mesoscale calculations show that there is near pressure equilibrium between reaction products and as yet unreacted explosive, but that their temperatures and densities are significantly different. Other authors have shown that reaction rate at continuum level depends on the number density of hotspots and burn speed. It is argued that hotspot number density depends on shock strength (represented by the non-reacted entropy) and the mesoscale calculations show that reaction products temperature best correlates with the burn front speed. By comparing the results of a mesoscale calculation with a continuum level calculation, it is shown that the two temperature ISE model is a reasonable approximation for the continuum level partially reacted equation of state.