Analysis of the effect on combustor noise measurements of acoustic waves reflected by the turbine and combustor inlet

Conference · Mon Oct 01 00:00:00 EDT 1984

OSTI ID:6932717

Huff, R G

The paper examines the measurement of noise from turbofan engines. Conclusions: (1) at idle engine speed no reflections from the turbine or combustor inlet occur; the infinite tube theory applies and yields excellent agreement with the data. (2) Above engine idle conditions, reflections from the turbine and combustor inlets occur and reasonable agreement between theory and narrowband combustor pressure spectra was found using a reflection factor of about 0.35 and a phase angle of 1.57 radians. (3) Spectrum shape is independent of measurement location at low frequencies but not at high ones.

• Research Organization: National Aeronautics and Space Administration, Cleveland, OH (USA). Lewis Research Center
• OSTI ID: 6932717
• Report Number(s): NASA-TM-83760
• Resource Relation: Conference: 9. aeroacoustics conference, Williamsburg, VA, USA, 15-17 Oct 1984
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
TURBOFAN ENGINES
NOISE
ACOUSTICS
AIRCRAFT
COMBUSTION CHAMBERS
MATHEMATICAL MODELS
REFLECTION
SOUND WAVES
ENGINES
560400* - Other Environmental Pollutant Effects