Hypersonic Aero-optic Analysis and imaging frameWorK (HAAWK)

The complex and harsh hypersonic environment, with high aerodynamic and thermal loads poses challenges to materials, structures and on-board sensors needed for target tracking, telemetry and communication. High surface temperatures require advanced optical window materials and possible cooling mechanisms. Aerothermal loads interacting with optical sensors include strong shock waves, causing strong, sharp density gradients, acting as a lens; turbulent boundary layer or wake flow; plasma effects due to high-temperature, non-equilibrium air behind shocks, resulting in background radiation, and in turn interacting with the sensor system. Optical window emissions and thermal deformation can also cause additional optical aberrations at the focal plane array. In this proposed effort, CFD Research will leverage past performance and experience in physics-based modeling and simulations to build a hypersonic aero-optic analysis and imaging framework (HAAWK), addressing aforementioned needs. In the Phase I Base period, turbulent wake flows will be analyzed and their aero-optical interference quantified. In Phase I Option, radiative effects will be added and relative importance of the key physical processes on the aero-optical interference will be quantified. In Phase I and continuing in Phase II, databases will be generated, to describe the image aberrations at the focal plane along a trajectory. This information can then be used by third-party sensor manufacturers to develop a real-time compensation algorithm, or, for software- and hardware-in-the-loop (SWIL/HWIL) simulations, supporting ground test and evaluation efforts.