Development and Application of the High Bandwidth Powered Resonance Tube

"The proposed Phase 2 program focuses on the development of Powered Resonance Tube (PRT) actuators for application to Active Flow Control (AFC). For effective control across the full operating envelope of an air vehicle, high bandwidth and authority arerequired. In Phase 1, a new variable-frequency PRT actuator concept was developed and its feasibility was demonstrated. In Phase 2, the new actuator concept will be refined in order to optimize its efficiency and effectiveness. Modified designs thatpermit greater geometric flexibility will also be explored. Experimental, computational and analytical methods will be used in the actuator development and refinement. Scaling information for future applications will also be developed. The PRT actuatoris applicable to both classes of AFC mechanisms: the excitation of instability waves, and forcing at higher frequencies in the inertial subrange of the turbulent flow. Specific applications to be investigated in Phase 2 are: (1) the enhancement ofmixing in a supersonic shear layer through the excitation of instability waves, and (2) the reduction of impinging jet unsteady loads, tonal and non-tonal noise by high-frequency forcing. An AFC preliminary design tool, which incorporates the PRT actuatorscaling information and employs a graphical user interface, will also be developed."