Unsteady Aspects of Shock-Wave/Boundary-Layer Interaction Resulting from Control Surface Deflection

A computational investigation of a Mach 6.9 turbulent flow near the juncture (cove) of a wing's trailing-edge and elevon was carried out. Turbulence was modeled using improved delayed detached eddy simulation (IDDES). The computational data were compared to the results of an experimental study, conducted by Deveikis and Bartlett, which simulated the flow over the windward surface of the NASA space shuttle. Flow visualization, surface variable comparison with experiment, and analysis of unsteady flow statistics were carried out. Reasonable agreement between prediction and measurement was obtained for time-averaged surface pressure and heat flux. Unsteady analysis of these quantities revealed spectra dominated by low-frequency energy content throughout the interaction region. A correlation analysis indicated coupling of the unsteady motions of the shear layer, shock wave, separation vortex, and flow reattachment. The results of the present study suggest that IDDES can be a valuable tool for the analysis of heating and unsteadiness in hypersonic gap flows.