A Systematic Characterization of the Structure and Dynamics of Transitional Shock/Boundary Layer Interactions
Abstract
With the recent trend towards design for extended laminar external flow in hypersonic boost-glide systems and lingering questions regarding the effectiveness of inlet trips, it can be expected that transitional shock/boundary layer interactions (XSBLIs) will play an increasingly prominent role in the development of new hypersonic capabilities. Although turbulent interactions have been the subject of significant research for more than 50 years and multiple NATO/AGARD international research initiatives, in contrast, the interaction between a shock wave and a boundary layer that is undergoing laminar-turbulent transition has received little attention. To date, it appears that a study of the dynamic behavior of transitional interactions in a manner similar to that which has been used to characterize turbulent interactions has not yet been undertaken. The members of the investigating team (U. Tennessee, Texas A&M, and Penn State) are proposing a systematic multi-facility investigation to address the following outstanding questions. • How does the dynamic behavior of the XSBLI evolve from the approximately steady, large separated region, laminar state to the unsteady, more compactly separated, turbulent state? • What are the critical scaling parameters of transitional interactions? • Do the XSBLI dynamics correlate with phenomena in the undisturbed transitional boundary layer? • Does the observed behavior of XSBLIs fundamentally change when such interactions occur in three-dimensional boundary layers with appreciable cross-flow components? To answer these questions, a comprehensive experimental initiative to document XSBLIs generated by cylinders and unswept compression ramps on flat plate boundary layers in four facilities ranging from Mach 1.8 to 6 will be undertaken, accompanied by complementary numerical simulations. A broad spectrum of experimental diagnostics including surface flow visualization, dynamic pressure measurements, hot-wire anemometry, particle image velocimetry, molecular tagging velocimetry, planar laser induced fluorescence, and vibrationally-excited NO monitoring. The insight and capabilities developed in the flat plat measurements will then be extended to study the behavior of XSBLIs generated by cylinders and fins in the cross-flow dominated boundary layers developed on elliptic cones representative of lifting body hypersonic configurations. Upon completion, this study will provide a new general characterization of the unsteady dynamics and resultant loads generated by transitional shock/boundary layer interactions that will be useful for the design and analysis of planned high-speed systems and technology demonstrators, including high-lift configurations with considerable boundary layer cross-flow and tripped airbreathing inlets.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2016
- Source ID
- N000141512269
Entities
People
- John D. Schmisseur
Organizations
- Office of Naval Research
- United States Navy
- University of Tennessee