Development of an elastic-plastic eulerian solver for high-speed deformations

High-speed elastic-plastic deformations of materials can be modeled by a set of hyperbolic conservation laws, which are similar to the compressible Euler equations for fluid flows. These elastic-plastic models can be used to simulate events such as high-speed impact of bodies on other bodies as well as penetration of a fast moving body into another body. In the present work, we describe the development of a new Eulerian elastic-plastic solver in our in-house code-Athena-RFX++. In particular, we develop and implement a new HLLC Riemann solver coupled with a Ghost Fluid Method (GFM) that can treat the elastic-plastic model equations. The solver can also handle multi-material problems, where each material is described by a different equation of state and solved with a different numerical solution method. Then, the new solver is tested against a classical one-dimensional benchmark from the literature. We demonstrate that our numerical solver solution is in excellent agreement with the benchmark results.