Numerical modeling of the action of an explosion on an iron slab

This article examines the explosion of a condensed high explosive (HE) by a flat Armco iron slab. The fundamental physical processes accompanying the nonstationary two-dimensional compression pulse propagation in a metal are analyzed, a mathematical model of the process is formulated, and its numerical characteristics are determined. A cylindrical charge of trinitrotoluene of 20 mm diameter and height, initiated at the axial point on the free surface, was mounted on a 10-mm-thick and 120-mm-diameter armco iron disk. A finite-difference method using a quadrangular computational mesh is employed. It is assumed that the process of detonation transformation occurs instantaneously and is characterized only by singularities in the equation of state. Numerical modeling of the loading of an iron slab by an explosion showed that the simple kinetic relationship proposed for the fracture computation will assure a realistic description of the fracture process. It is determined that the progress of a reversible polymorphic transformation in the specimen material substantially influences the nature of its fracture by explosion. The magnitude of the strain on the strength properties of the material must be taken into account in order to achieve a detailed description of the fracture.