Drop weight impact thermomechanics with GnarlyX multi-physics hydrocode simulations

Drop weight impact experiments are critical in assessing handling safety when developing new explosives and formulations. However, they convolute large deformations, heat generation and chemistry that lead to a "Go" or "No-Go" signal for the onset of reactions. Although the current interpretation is useful in screening for high explosive (HE) safety and sensitivity, we push towards a fundamental understanding of these tests in investigating the thermomechanical conditions that lead to a chemical reaction. This talk focuses on large deformation and heat localization behavior through multi-physics hydrocode simulations of a related system, the Viscoplastic flow Ignition and Propagation Imaging of Reactions (VIPIR) experiment. We use GnarlyX, a multi-dimensional, multi-material and strength hydrodynamics code for high performance computing platforms. It is based on a Helmholtz free energy formulation which gives thermodynamically consistent temperature. We simulate the crushing of an HE sample between two anvils with simple to complex geometries and material interaction. This approach is necessary in estimating the computational expense of a suite of multi-physics simulations important in revealing the mechanisms that lead to temperatures sufficient for ignition.