Initial Experimental Validation of an Eulerian Method for Modeling Composites

Impact loading response of unidirectional and plain weave fiber reinforced polymer composite materials is typically modeled using a Lagrangian method such as the finite element method. However, these methods often lack a coupled equation of state. In anisotropic materials, the pressure (equation of state) and deviatoric (strength) portions of the stress tensor are coupled: a shear stress can produce a volumetric response and a volumetric strain can produce a shear stress. High-velocity impacts of composite materials instigate a coupled pressure and stress response, so an equation of state is important in determining the non-uniform stress response of the material. A new composite model, which couples the pressure response to the constitutive response of the material, has been implemented in an Eulerian large deformation, strong shock wave, solid mechanics code. Experiments of steel projectiles perforating composite targets were numerically simulated to begin to validate this new composite model. This paper will discuss the coupled equation of state and strength response, and compare the results of these experiments with the results predicted by the model.