A comparison between entropy, temperature and pressure-dependent reactive-burn models

The CREST reactive-burn model has been remarkably successful in modelling shock initiation and detonation propagation behaviour in plastic-bonded explosives. This has been achieved by using a reaction rate that depends on shock strength (measured using a function of entropy of the unreacted explosive) and time since the shock passed, and not on evolving parameters of the flow like pressure or temperature which are the basis of most reactive-burn models. This paper investigates the advantages and disadvantages of entropy, temperature or pressure-dependent reaction rates for simulating a variety of one and two-dimensional shock initiation phenomena.