Description: Flight control, structural reliability, and efficiency depend critically on the ability to assess the time-accurate unsteady aerodynamic loads and moments for each lifting surface under nominal and adverse flow conditions. Tao Systems and California Institute of Technology propose to develop a flow control system that utilizes advanced sensors and a vorticity state estimator (VSE) to reach flow states unattainable without continuous control feedback. The flow control scheme enables manipulation of the vorticity state to achieve performance objectives, such as short take-off/landing through controlled aerodynamic lift at angles of attack near stall.

Benefits: Vorticity-based flow control system will enable a number of revolutionary capabilities across a wide speed range, including, but not limited to: (1) shorter take-off and landing, (2) safe, reliable aircraft operation in turbulent condition, and (3) larger passenger and cargo capacity. The primary difficulty in all three revolutionary capabilities is the uncertainty in aerodynamic load & moments generated by the airstream in design and off-design conditions, e.g., turbulent flows, high angles of attack and unsteady flows. Measuring the unsteady aerodynamic loads/moments through the vorticity state reduces the aerodynamic uncertainty enabling the aircraft to timely, robustly compensate for the adverse, unsteady flow conditions. Therefore, the proposed innovation could be of significant interest to the aircraft civilian industry.

For national security, the ability to cruise efficiently at a range of altitude, enabled by a substantial increase in cruise lift-to-drag (L/D) ratios over today's high-altitude reconnaissance aircraft, is vital, providing sustained presence and long range. Vorticity-based flow control would enable the efficient, robust active control of adaptive, lightweight wings to optimize lift distribution to maximize L/D. Cost-effectively improving the energy capture and reliability of wind turbines would help national renewable energy initiatives. A vorticity state estimator could provide output for control feedback to mitigate the turbine blade lifetime-limiting time varying loads generated by the ambient wind.