Abstract
This paper reports on a technology demonstration test of a GEAE F404-400 engine with low aero-performance impact noise suppression devices. The test was conducted at the Naval Air Warfare Center Aircraft Division at Lakehurst N.J. The engine was mounted on a modified engine support stand that permitted aero-performance assessment and measure of far field acoustics. The noise suppression concepts investigated involved outer divergent flap chevron extension, internal engine corrugated seals, and microjet injection of either nitrogen or water droplet spray. Noise reduction at the peak energy emission angle was 2 dB for chevrons, corrugated engine seals, and water droplet spray. The corrugated seals were found to eliminate shock generated noise. The chevrons decreased thrust between 1½. The water droplet spray did not affect thrust, and the corrugated engine seals enhanced thrust by ½%. Both the water droplet spray and corrugated seals reduced Infra-Red plume emission.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
