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Based on the 1-D elastic–plastic reactive hydrodynamic code Simplified Stretch Sin, a magnetohydrodynamic (MHD) version SSS/MHD has been developed. The new code is of multifield coupling, making use of the Resistance-Inductance-Capacitance circuit equations related to loading currents and others. To calculate MHD and circuit variables consistently and simultaneously, on the basis of Faraday’s law, the relations between loading currents and magnetic flux in configuration cavities, variation in total magnetic flux and back electromotive force, and an iteration procedure are employed. The sample configurations in magnetically driven isentropic compression experiments (ICEs) here consist of parallel slabs and cavities, in which the step targets are a pair of slabs symmetrical to loading electrodes and of the same sample material but different in thickness. Self-consistent MHD and circuit calculations for ICE step targets of aluminum, tantalum, and plastic binder explosive is reported in this paper. The results agree with the measured ones well, including loading current profiles and velocity histories on samples’ free surface or optics window interface. Since the input data for this code are geometric sizes, material parameters, and original circuit parameters only, its results are independent of measured or empirical data, and could be helpful in design and prediction of ICE or other experiments. [ABSTRACT FROM PUBLISHER]

[Display omitted] • A mechanical-thermal-chemical coupled peridynamic modeling is developed. • Major damage feature is well captured by current model. • Damage and ignition of PBX is investigated using developed PD model. • Ignition location and corresponding mechanism are analyzed. • Relationship between mechanical damage and temperature is revealed. The major damage and ignition features of polymer bonded explosive (PBX) subjected to punch loading are captured by developed mechanical-thermal-chemical coupled multiphysics peridynamics (PD) framework. The framework integrates a four-step chemical reaction kinetics model and thermal effect induced by friction due to mechanical damage. The heterogeneous microstructures are explicitly taken into consideration, enabling different fracture modes such as inter-granular and trans-granular fractures can be captured. Results show that the dynamic damage is characterized by the formation of a triangular-shaped dead zone, in agreement with Prandtl's prediction. Flow field analysis implies that the changes of flow field in the transition zone are responsible for the temperature rise. The riskiest positions to ignite are the boundaries of the triangular-shaped dead zone and the region inside the dead zone. Furthermore, sliding friction dissipation associated with trans-granular fracture and inter-granular fracture are responsible for the ignition along the boundaries of dead zone and inside the dead zone, respectively. The analyses on mechanical damage and temperature rise reveal that mechanical damage precedes the temperature rise. Simulation results provide novel insight into ignition mechanism of PBX, which can be used to construct more accurate physical model of non-shock ignition of PBX. [ABSTRACT FROM AUTHOR]