Fluid-Structure Interaction on a Thin Panel Including Shock Impingement Effects

Abstract

An experimental methodology was designed to explore the aeroelastic response of a thin, buckled panel to turbulent flows with and without a shock/boundary layer interaction (SBLI). The approach combines a systematic testing strategy with state-of-the-art full-field, non-contact measurement techniques. Measured time histories of the full-field displacement from three-dimensional digital image correlation (DIC) and the panel velocity showed multiple instances of co-existing, nonlinear panel responses. Periodic and chaotic post-flutter oscillations with and without SBLI were captured. Aeroelastic simulations of the thin panel were also evaluated relative to the experimental data. The fully coupled simulation framework relies on the quasi-steady enriched piston theory model for the mean aerodynamic pressure coupled with a nonlinear structural reduced-order model. The system’s sensitivity to the cavity pressure as well as temperature differential between the frame and panel were investigated. The simulations reasonably predicted the onset and frequency content of the post-flutter response for a range of conditions, albeit with an increase in the oscillation amplitude. Chaotic and periodic oscillations occurred for the buckled panel in the absence of SBLI. The panel behavior transitioned to periodic when an attached SBLI was introduced over the surface, with a majority of the oscillations centered about the three-quarter chord.