Characterization of Particle-Surface Impacts on a Sphere-Cone at Hypersonic Flight Conditions

Abstract

This study utilizes in-situ data of stratospheric particle size distributions to understand particle-surface impacts at hypersonic flight conditions. Particle diameters range from 0.2 to [Formula: see text]. Simulations are performed to track Lagrangian particles through the flowfield and statistically gather the characteristics of particles that impact the surface. Probability density functions in terms of surface-impact locations, particle sizes, velocities, incident angles, and kinetic energies are presented. The results indicate that sub-micrometer-diameter particles most frequently impact the nosetip of the vehicle at a range of velocities that tend toward the freestream velocity at higher altitudes. However, it does not appear that sub-micrometer particles significantly contribute to the net surface-impact kinetic energy. It is shown that larger particles between 6 and [Formula: see text] are responsible for the majority of net surface-impact kinetic energy, despite these surface-impact events being infrequent.