Aeroelastic Stability Characterization of a Slender Model Under Planar Shock Impingement in Mach 5 Flow

This experimental study characterizes the aeroelastic stability of a single degree-of-freedom (SDOF) model under planar shock impingement in a Mach 5 blowdown wind tunnel. An ambient excitation method coupled with different output-only system identification algorithms was used to measure both the static and dynamic stability of the model. A Laser Doppler Vibrometer (LDV) was used to measure the displacement of the model in the free-stream flow and to compare with predicted structural behavior using steady-state computational fluid dynamic (CFD) results and Newtonian flow theory. The trend of measured deformation showed good agreement with predictions for two values of model flexibility. The measured free-stream aerodynamic damping was consistently over-estimated using Newtonian flow theory. The structural behavior under shock impingement at two different locations shows a nonlinear fluid-structure interaction whose aerodynamic forcing adds static and dynamic stability to the system.