Advanced Unsteady Flow Control (Keynote Paper)

A general description, underlining some of the defining principles behind the revolutionary advanced unsteady propulsive system, is provided. The developed system is a large amplitude unsteady propulsion that leaves free trailing vorticity of magnitude O (ε⁰) per unit of time down-stream of the flow. Having multiple degrees of freedom (sixteen for the scaled-down prototype) the system has been designed to efficiently operate in transitional and unsteady flows through sensing and capturing the energy of flow perturbations and turbulence in addition to that of the free-stream. Numerical studies, backed by experimental data, have demonstrated the high efficiency gain of the system in comparison to the conventional turbomachinery.