Enhanced Modeling and Simulations of Hypersonics

Endo-atmospheric flight at hypersonic speeds creates an extraordinarily harsh aerothermal environment which may lead to the formation of an ionized plasma layer around some parts of the vehicle. Free electrons in this plasma layer are formed via a combination of collisional ionization and oxidative reactions with carbon products and contaminants. From the perspective of electromagnetic interactions, the plasma and hot gases effectively function as a layered dielectric material which may reduce the radar cross section (RCS) via absorption and/or modify the range profile via reflection. As such, computing RCS signatures of hypersonic vehicles requires a holistic approach including definitions of vehicle trajectories and reentry corridors, vehicle geometries for input to the computational fluid dynamics (CFD) and plasma modeling simulations which are then used to calculate dielectric properties and compute the RCS. These collection inputs will then be used as Monte Carlo (MC) variables for input to the IERUS toolbox Monte Carlo Uncertainties for RCS Phenomenology (MURPH) which evaluates RCS uncertainties due to geometry and material variations