This research addresses techniques for active suppression of pressure oscillations in an open cavity. Flow over an open cavity, as in an aircraft weapons bay, can cause excessive sound pressure levels that lead to failure of system components. Passive suppression techniques can only be optimized for a single condition; thus, and active control system is desireable tat adapts to to changing conditions. This effort focuses on the development of a prototype active suppression system and advanced theoretical modeling of the problem. The control system consists of three parts: (1) novel actuators for unsteady forcing of the cavity shear layer, (2) acoustic sensors in the cavity, and (3) an adaptive feedback control system. The modeling will investigate (1) shear-layer-growth nonlinearities via Parabolized Stability Equations, (2) shear-layer receptivity, an (3) the acoustic source via analysis of CFD simulations and experimental data. This modeling will lead to both a better understanding of cavity and oscillations and a computationally inexpensive prediction tool for rectangular cavities. In addition, the model will assist in the development of an adaptive control system. While targeted at weapons bay, the control system is applicable to virtually any flow-separation control problem and therefore possesses significant commercial potential.
Keywords: Laser Radar Optical Waveguides Optical Interconnects Integrated Photonic Devices
