Accession Number:

ADA076253

Title:

Jet Engine Demountable Test Cell Exhaust System Phase - Coanda/Refraction Noise Suppression Concept - Advanced Development.

Descriptive Note:

Technical rept. Jul-Dec 76,

Corporate Author:

BOEING WICHITA CO KS

Personal Author(s):

• Ballard ,R. E.
• Byers ,W. F.
• Armstrong,D. L.

Report Date:

1979-04-01

Pagination or Media Count:

91.0

Abstract:

The successfully demonstrated Coandarefraction air-cooled exhaust noise suppressor system is applied to the Navy requirement for effective exhaust noise suppression in jet engine demountable test cells. The technical approach consists of analytical studies and one-sixth scale model tests using simulated afterburning engine exhaust. Revisions are made to the previously developed system to improve noise suppression capability while reducing the system overall size and initial cost. Revisions include moving secondary air inlets to reduce enclosure size and improve cooling, shortening the Coanda surface to provide more acoustically treated exhaust stack and providing variations in exhaust stack configuration such as single and dual acoustic splitters and acoustic wedges up the back wall. Extensive data were recorded and analyzed to identify the aerothermodynamic and acoustic trends related to these configuration changes. Results present recommendations for an air-cooled Coandarefraction exhaust system for application to demountable test cells. Author

Descriptors:

• *JET ENGINE EXHAUST
• *SUPPRESSORS
• *JET ENGINE NOISE
• ACOUSTIC MEASUREMENT
• ACOUSTIC EQUIPMENT
• WEDGES
• AEROTHERMODYNAMICS
• GROUND SUPPORT EQUIPMENT
• TEST FACILITIES
• ACOUSTIC REFRACTION
• EXHAUST PIPES
• AIR COOLED
• BAFFLES
• COANDA EFFECT

Subject Categories:

• Terminal Flight Facilities
• Acoustics
• Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE