Numerical simulation of the interaction of oscillating oblique shock waves and turbulent boundary layers over flexible and rigid surfaces*

Coupled fluid-structure interaction (FSI) simulations that integrate a finite-volume wall-modeled LES (WMLES) flow solver and a finite-element (FEM) solid mechanics solver are used to study the interaction of forced oscillating oblique shocks impinging on turbulent boundary layers (TBL) developed along rigid and flexible panels. The methodology of the coupled solver enables long integration times needed for spectral analysis while maintaining physical fidelity. Simulations are performed for a Mach 3 TBL interacting with a dynamic shock-expansion system generated by a wedge periodically rotating between 15.5 and 17.5 degrees, at different oscillating frequencies ranging from 50 to 800 Hz over rigid and elastic panels. The deflection of the flexible panel is found to be excited by wedge oscillation frequencies close to the primary natural frequency of the panel. Increasing the oscillation frequency over both rigid and flexible walls results in an attenuated response of the flow separation bubble. The gain and phase angle of several quantities of interest of the STBLI are studied as a function of the wedge oscillation frequency.