Thermal Explosion of HMX Using a Subscale Frank-Kamenetskii Model with Detailed Chemical Kinetics

We present a subscale model for conductive burning in an explosive material featuring a complex kinetic network. Our approach is based on the Frank-Kamenetskii (FK) thermal explosion model, with numerical solutions obtained using the method of weighted residuals (MWR), as originally proposed by Bennet et al. [J. Mech. Phys. Solids, 46, 2303, 1998]. The subscale model incorporates localized heating of the solid energetic material due to grain-scale phenomena like frictional heating of small cracks, resulting in ignition. This framework, coupled to a physically-based kinetic model for the reaction, is applied to the problem of conductive burning of HMX. We present preliminary results from our studies, including propagation velocities for the reaction front under varying conditions, and discuss future extensions and applications of this model.