Core noise from gas turbine exhausts
- Creators
- Cumpsty, N. A.
- Marble, F. E.
Abstract
There is abundant evidence to show that the exhaust noise from gas turbines contains components which exceed the jet mixing noise at low jet velocities. This paper describes results of a theory developed to calculate the acoustic power produced by tempetature fluctuations from the combustor entering the turbine. With the turbine Mach numbers and flow directions at blade mid-height, and a typical value for the fluctuation in temperature, as parameters it has been possible to predict the acoustic power due to this mechanism for three different engines. In all three cases the agreement with measurements of acoustic power at low jet velocities is very good. Similarly, based on a measured spectrum of the temperature fluctuation, the prediction of the acoustic power spectrum agrees quite well with that measured.
Additional Information
© 1977 Published by Elsevier Ltd. Received 10 October 1974, and in revised frm 27 May 1977. This work has been heavily dependent on the co-operation of the aeronautics industry. The authors wish to thank Rolls-Royce Limited, for aerodynamic and noise data for the Spey 512 and Olympus 593, Pratt and Whitney Aircraft for aerodynamic data on the JT8D, and the Boeing Commercial Airplane Company for noise measurements from the JT8D. They would in particular like to express their gratitude to R. R. Dils of Pratt and Whitney Aircraft whose guidance on combustion chamber behaviour was invaluable.Additional details
- Eprint ID
- 21339
- DOI
- 10.1016/0022-460X(77)90031-1
- Resolver ID
- CaltechAUTHORS:20101214-073031680
- Created
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2010-12-14Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Guggenheim Jet Propulsion Center
- Other Numbering System Name
- Guggenheim Jet Propulsion Center