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This experimental study aims to investigate and compare unsteady surface pressure fluctuations on rigid and compliant panels under a shock-wave/boundary-layer interaction (SBLI) generated by a 20o compression ramp in a Mach 2 wind tunnel. The compliant panel was made of 1mm thick polycarbonate and had a first mode resonant frequency of 407 Hz. High-speed simultaneous pressure-sensitive paint (PSP) and digital image correlation (DIC) techniques allow for examination of the panel surface pressure and panel displacement, respectively, with acquisition frequencies of 20 kHz and 5 kHz respectively. The PSP measurements were also made on the face of the rigid compression ramp and so the effect of fluid-structure interaction on the reattachment dynamics could be explored. The rigid panel pressure measurements demonstrated the spectral content inherent to the SBLI. Spectral analysis of the surface pressure fields revealed that the SBLI shock foot and separation shear layer behave as low- and high-frequency filters, respectively, and the compliant panel showed the similar behavior with the peak frequency at the first mode frequency of the panel (~407Hz). The spectral comparison of pressure fields also depicted that the other modes of the structural panel affected the flow ( at frequency 624 Hz) near the compliant panel’smore »mid-region. The results indicate the panel dynamics have a strong effect on separation- and reattachment-flow dynamics. Modes obtained by spectral proper orthogonal decomposition (SPOD) show good agreement with modes obtained from bandpass filtered displacement and pressure fields.« less