Modeling and Closed-Loop Control of Complex Flows Over Aerodynamic Surfaces

The use of active flow control can reduce or eliminate the number of aerodynamic control surfaces in aircraft. Elimination of control surfaces results in a reduction of weight and drag, as well as radar observability. Recent advances in MicroElectromechanical Systems (MEMS) technology have rendered it a feasible alternative for unsteady flow sensing and control. This project will be performed jointly by Scientific Systems Co. and Prof. Rediniotis from Texas A&M University, and will demonstratethe use of MEMS for closed-loop flow control. In particular, a delta wing is controlled by actively inducing or delaying Vortex Breakdown (VBD) so as to globally affect the flow over the wing in a desired way. The feedback mechanism is hingeless andconsists of MEMS-based flow sensors and small Pneumatic Vortex Control (PVC) jet actuators. During this effort, we will develop modeling and control design algorithms for active flow control. Proposed Phase I tasks include: (a) acquisition of unsteady flowdata, (b) control-oriented reduced order unsteady flow modeling using wavelets, indicial functions, and system identification techniques, (c) feedback controller design and numerical evaluation using robust control techniques, and (d) planning forreal-time flow control demonstration in Phase II. Unsteady flow data will be acquired from the facilities in the fluid dynamics laboratory at Texas A&M University.Active control of vortical flow fields has applications in jet engines and turbomachinery,rotorcraft, air traffic control, and UAV formation flying. MEMS-based sensing and actuation technology has applications in NDE of structures, and bio-mimetics.