Large deformation GnarlyX hydrocode simulations of the drop weight impact experiment

We aim for new perspectives on the complex underlying mechanisms that lead to the onset of

chemical reactions in drop weight impact experiments which have been studied for several

decades. In these experiments, a hammer with drop velocity ~1 m/s delivers energy to a 40 mg

sample over hundreds of microseconds and converts kinetic energy to thermal energy that can

initiate reactions in the explosive with an audible deflagration. Large deformation and heat

generation in the sample critically depend on the material properties of the HE although the exact

thermomechanical conditions which lead to a “Go” or “No-Go” are unclear. Our approach

toward identifying the leading mechanisms in this complex system is through multi-physics

hydrocode modeling of new transparent anvil drop weight impact experiments under

development at LANL. We use GnarlyX, a LANL hydrocode for large deformation

thermomechanics, to generate a suite of multi-material and strength hydrodynamics simulations

of the dynamic response of the HE to impact. In developing material models with increasing

complexity, we consider the thermomechanical conditions which lead to high temperature

distributions within the sample.