Computational analysis of the interaction of particles with the shock structure surrounding hypersonic aerial vehicles

When hypersonic aerial vehicles re-enter the atmosphere they encounter rain droplets, mist, fog, meteoroids, and ice crystals present in precipitating clouds. An impact with these minute objects at such high speeds can cause significant/catastrophic damage to the vehicle's outer surface. Liquid droplets also tend to disintegrate into smaller droplets and create a mist that can further damage the vehicle. The distribution of particles of various diameters encountering a shock and the droplet deformation that follows - which are both crucial for estimating the impact event is not well-understood. To this end - the present study produces a DNS-like Euler-Lagrangian (EL) coupled, compressible, density-based solver with the Clift-Gauvin particle drag model (best performance for high-speed flows) to produce a comprehensive statistical analysis of the positions and conditions of particles of different diameters. The understanding gained from this study is intended to form the foundation of future CFD of isolated raindrops and ice crystals. The simulations are based on a double-wedge geometry with conditions encountered at 20 kilometers altitude with a large number of particles in the range of 1 to 1000 microns considered.