Simulations of Ash and Sand Impact on a Hypersonic Forebody
Brian J. Connolly, Eric Loth
Abstract
Hypersonic vehicles operate at extreme environments at narrow margins of safety. High-speed flight in the atmosphere when volcanic ash and other meteorological particles are present can cause damage to these vehicle surfaces, impairing heat transfer and damaging sensitive components, leading to failure. Upon surveying typical conditions for solid particles that might be encountered, it was determined that A2 test dust is a reasonable representation in terms of particle density, shape, and size distribution. A set of high-fidelity simulations was conducted with a hypersonic forebody to improve our understanding of the particle trajectories and impact energies as a function of particle size at relevant flight conditions. The results indicate that particle sizes between 4 and are responsible for the majority of the net surface-impact energy. It was also found that effects of compressibility and shape on particle drag can be significant within the boundary layer.