AEM Special Seminar: Experimental Investigations of Fluid Structure Interactions in Hypersonic Platforms
Abstract: My research group focuses on addressing various propulsion and aerodynamics phenomena to achieve ultrafast air mobility and commercial space access. In this talk, I will present our ongoing efforts to investigate the fluid structure interactions in hypersonic platforms. Specifically, the talks explore the dynamics of an impinging shock boundary layer interactions (SBLI) flowfield to a thin panel executing small amplitude elastic oscillations (oscillation amplitude much smaller than the incoming boundary layer thickness as well as panel thickness). This unit problem provides crucial understanding of the genesis of the macro-scale flow response with larger amplitude vibrations and ultimately to feedback coupling between flow and structures. The oblique shock was generated by an 8-degree shock generator placed incident on a Mach 2.5 flow. The shock strength was large enough to generate a nearly two dimensional mean separation and the pulsations of the separated bubble straddled several elastic bending modes of the thin panel. As a critical component of this research, the first demonstration of simultaneous multivariate measurements of panel surface pressure, panel center-span deflection, and off-body velocity field are also presented. Together, these measurements provide comprehensive information on the FSI phenomenon from both aerodynamics and structural dynamics perspectives.
Summarily, at the low amplitude panel vibrations, there is no change in the mean separation size, which was confirmed by multiple measurements. Interestingly, the separation shock oscillations appear to pick up some of the panel resonance modes frequencies. Detailed spectral maps of panel surface pressure reveal further information about how the shock motions can eventually result in macro-scale response.Bio: Dr. Venkat Narayanaswamy is an Associate Professor at Mechanical and Aerospace Engineering Department of NCSU, where he has served as a faculty since 2012. He directs a