Physics of Pervasive Shock-Turbulent Interactions in Hypersonic Vehicles
Hypersonic flight has been recognized by all services as a critical enabler of time-critical strikes against mobile or hardened targets, hostile airspace survivability, reliable space access, and as an offset technology  to boost conventional deterrence. This has led to numerous weapons programs such as the Army's potentially truck-launched Long-Range, Hypersonic Weapon (LRHW).  The Army's analysis of such vehicles specifically calls out the implications of several crucial but poorly characterized phenomena, including shock boundary layer interactions, uncertainties in heat transfer prediction, thermal protection, and air-breathing inlet propulsion design. These substantial uncertainties, and consequent conservative design choices, are a primary cause of rising costs, which has led to sobering assessments of these compellingly advantageous but expensive systems. 

Results from this Frontier project constitute a comprehensive high-performance effort to generate fundamental and applied insights into the development and hypersonic performance in the High-Speed Army Reference Vehicle (HARV) class, comprised of finned projectiles and cropped-delta fins. Publicly released results from the first year of the project use an optimal mix of fidelities (Reynolds-Averaged Navier-Stokes, Large Eddy Simulations and Direct Numerical Simulations) and highly-accurate, efficient and scalable algorithms and include: 1) Full vehicle simulations at a range of angles-of-attack and sideslip that display the complex structure of the flow, including various vortices and shock/boundary layer interactions; 2) Uncertainty reduction using high-quality experiments being performed at NASA Glenn Research Center and a complementary Army Research Office task; 3) Mechanisms associated with transition-to-turbulence on the vehicle forebody; and 4) Benchmark quality databases of tunnel conditions necessary for proper problem setup, reduced-order modeling, scaling to free flight, and developing turbulence models suited for codes such as CREATE-AV.  Advanced post-processing techniques assure the extraction of critical insights from the large databases with broader implication than the specific configuration considered for concreteness.  Overall, these results demonstrate substantial progress in filling key gaps in the knowledge-base that ultimately should help reduce unit costs in hypersonic system development.
IMPACT
Accomplishment: Used cutting-edge highly scalable methods to simulate and analyze complex nonlinear interactions crucial to the development of hypersonic weapons; Result: Generated lift, drag and moment data on Army-relevant vehicle, with uncertainty assessment, to clarify ground test observations. Findings reduce uncertainty currently requiring conservative design and prohibitive costs.
PRESENTER
Gaitonde, Datta
gaitonde.3@osu.edu
937-545-2223
The Ohio State University
CO-AUTHOR(S)
Duan, Lian
duan.322@osu.edu
Poggie, Jonathan
jpoggie@purdue.edu
CATEGORY
Comp Fluid Dynamics
SECONDARY CATEGORY
Big Data
SYSTEM(S) USED
Carpenter (ERDC), Narwhal (NAVY), Ruth (ARL)