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

Abstract

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.

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

Citation Formats

Huff, R.G. Analysis of the effect on combustor noise measurements of acoustic waves reflected by the turbine and combustor inlet. United States: N. p., 1984. Web.
Huff, R.G. Analysis of the effect on combustor noise measurements of acoustic waves reflected by the turbine and combustor inlet. United States.
Huff, R.G. 1984. "Analysis of the effect on combustor noise measurements of acoustic waves reflected by the turbine and combustor inlet". United States. doi:.
@article{osti_6932717,
title = {Analysis of the effect on combustor noise measurements of acoustic waves reflected by the turbine and combustor inlet},
author = {Huff, R.G.},
abstractNote = {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.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1984,
month =
}

Conference:
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