CLOSED LOOP ACTIVE CONTROL FOR CAVITY ACOUSTICS

To increase the range and payload of both existing and future aircraft, while maintaining or increasing mission survivability, weapons must be carried in low drag/low observable configurations. Existing external weapons carriage technology accounts for as much as 30% of total vehicle drag and prohibitive increases in radar signature. Internal weapons carriage solves signature r issues, but substantially increases aircraft size while limiting weapon payloads to the size of weapon bays. New innovative and novel ways of both internal and external weapons carriage will be crucial to fighters of the next century. However, the new internal bays create a challenge to develop methods to suppress and control the internal flow induced acoustic environment -in the weapons bay. The objective of the current wind tunnel test programwas to test pulsed fluidic injection at the leading edge of the cavity at --higher ifrequencies and evaluate closed -loop control. Suppression effectiveness was shown to be frequency dependent and closed loop control was shown to optimize suppression for most set of constraints.