Airborne Laser Laboratory Exhaust Channel Acoustic Analysis.

摘要

A wind tunnel investigation was performed to determine the acoustic characteristics of two alternative exhaust channel configurations for the Airborne Laser Labratory (ALL) gasdynamic laser. Models of the rectangular opening cavities were exposed to external flow in the Mach number range of 0.40 to 0.85 under the no-exhaust flow condition. Several shallow cavity resonance phenomena were identified in addition to both open and closed organ pipe deep cavity resonances. Both porous fence and low mass flow rate front lip blowing were found to be effective in resonance suppression. (Author)