Surface Film Instrumentation System for Vortex and Structural Dynamic Measurements

A surface film instrumentation (SuFI) system will be developed to measure, in real time, vortex dynamics using advanced non-intrusive hot-film sensors. An innovative 5-element hot-film sensor design will be used to determine the surface streamline direction resulting from the off-surface, three-dimensional vortical flows. Wind-tunnel tests will be conducted on a generic double-delta wing model instrumented with multi-element hot-film sensing system to extract dynamic characteristics and the surface signatures of wing leading-edge vortex (LEV), shear-layer instabilities, vortex breakdown, and bifurcation regions that define the flow separation and reattachment lines. Simultaneously, the structural response of the vertical tails to the LEV impingement will be measured with straingages. Results from wind-tunnel measurements will be used to establish a correlation between vortex aerodynamics and structural response. A realistic aircraft configuration will be used in Phase II R&D effort to investigate unsteady aerodynamic-structural interactions and to establish design parameters for developing a stand-alone real-time prototype SuFI system consisting of hot-film sensors, constant voltage anemometers, and associated hardware and software.