S.A.L. Glegg

This paper describes some important issues concerning the prediction of broadband fan noise which occur when the fan tip speed approaches the speed of sound. The theory for broadband noise can be developed in terms of a modal expansion of the sound field but it is shown that this results in an extraordinarily large number of modes which have to be summed for the high speed case. The issue of quadruple sources is also discussed and it is shown how these are concentrated on the surfaces of the blade and the surfaces of shock surfaces which may be present. Examples are shown of the relative importance of blade and shock associated broadband noise.

First Joint CEAS/AIAA Aeroacoustics Conference, München, 1995

Conference Paper

englisch

21,0 x 29,7 cm, 10 Seiten

DGLR-Bericht, 1995, 1995-01, First Joint CEAS/AIAA Aeroacoustics Conference - Proceedings; S.141-150; 1995; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

aeroacoustics

Bibliothek

1995