Temperature-based model for condensed-phase explosive detonation

Simple reactive flow models for condensed explosives have four requirements: two equations of state (EOS), one for the unreacted condensed-phase explosive, and one for its detonation products, a reaction rate law that converts the explosive in products and a mixture rule to compute the biphasic partially reacted states. Generally, the chemical reaction rates are governed by local temperature. Nonetheless, temperature fields are scarcely known, especially in detonating condensed-phase explosives. Hence this quantity is not provided by the usual unreacted explosive EOS with the required accuracy. As a consequence, for shock initiation and detonation phenomena, rate laws are based on easily measurable properties such as pressure, compression or particle velocity. In this work, we build an EOS for a TATB-based explosive that provides a better estimate of the shocked explosive temperature. This EOS is derived from ab initio simulation results of monocristalline TATB. Then the well-known pressure-based WSD reaction rate law is rewritten to be temperature-dependent. This model is expected to give interesting results as regards shock desensitization and initial conditions variations while remaining very accurate for detonation propagation. Preliminary results will be shown.