Computational modeling and wave propagation in media with inelastic deforming microstructure

Abstract
A phenomenological continuum model for computational use has been developed to describe large amplitude transient wave propagation in heterogeneous multi-component materials. A key feature of the model is a physics-based treatment of the continuum response of microstructural components with markedly dissimilar elasticity and strength properties. A fundamental premise of the modeling effort is reliance solely on widely available dynamic material property data including Hugoniot equation-of-state and Hopkinson pressure bar strength data through either direct application or physically plausible theories. Average nonlinear iso-pressure and iso-strain solutions provide bounding responses of the multi-component material. Compressive deformation under pressure and concomitant dissipation is treated through methods of irreversible phase transformation. The model has been incorporated into a multidimensional Eulerian finite-difference shock physics code and used to examine the response of selected materials to dynamic loads.