Sensing of Shock Wave Boundary Layer Interaction using a Vibratory Physical Reservoir Computer

Shock wave boundary layer interactions can create unsteady flow disturbances that can be detrimental in many supersonic flow applications. Typical applications require high sensor density and computational cost to capture the broad spatial and temporal scales spanned by unsteady flow features. Vibratory Physical Reservoir Computers (PRC) can overcome these challenges by using the non-linear dynamics of vibratory structures to sense and process features of the fluid structure interaction, all with minimal digital computation. This study uses a vibratory PRC under a shock wave impinging on a turbulent boundary layer in a Mach 1.4 free stream duct flow. The vibratory PRC is a metamaterial made up of non-linear unit cells which are excited by the unsteady flow features of the shock wave boundary layer interaction. The physical structure of the PRC is specifically designed to be responsive to select relative frequencies of the flow phenomena. The output of the vibratory PRC is trained to be representative of the input flow unsteadiness. This allows for estimation of the flow features driving the fluid structure interactions using the vibratory PRC as the sensor. Specifically, this will be conducted through synchronous flow imaging with the output of the vibratory PRC.