Compressible Particle-Particle Interaction Implementation in Hydrocodes

Ejecta physics plays an important role in materials shocked by high explosives. When a shock impacts a rough surface of a solid material and melts it, the Richtmyer-Meshkov instability grows perturbations on the surface, which can eject particles. After release, the ejecta travel through the post-shock compressible flow. To simulate a large number of ejecta particles, an Euler-Lagrange approach is preferred, which requires modeling the subgrid-scale physics involved with fluid-particle interactions. We generalize the previous work from Hsiao et al. (Physical Review Fluids, 2023) to a system of moving particles subject to any loading shock in a fully functional hydro code. The following improvements were made: (1) The particles are allowed to move (2) Non-planar shocks are accounted for along with allowing for variable shock speeds. The generalized algorithm was tested with particle-resolved simulations for canonical test cases. The results of these tests are discussed and analyzed.