K. Takahashi, S. Kaji

An analysis is performed on the sound generation due to the interaction between flow turbulence and plate edges. Two acoustic fields are treated; one is the well known trailing edge noise and the other is the sound generation from tandemly situated trailing and leading edges. Applying the Wiener-Hopf technique, we obtain a calculable solution to the sound pressure proportional to the amplitude of the incident vorticity wave in each problem. The trailing edge noise field exhibits dipole-like cardioid directivity and its sound pressure level is ascertained to be dependent on the fifth power of flow velocity at low Mach numbers. However, such dependence does not hold at higher Mach numbers, where the generated noise level rises more rapidly as the flow velocity increases. When a leading edge is placed in the downstream, the calculated acoustic field shows complicated peaks and troughs because two coherent sound waves radiate from the trailing and leading edges. We clarified the phase difference between each sound wave and vorticity wave and explained the selective response mechanism which produces edge-tone like frequency dependence in this flow field.

DGLR/AIAA 14th Aeroacoustics Conference, 1992

Conference Paper

englisch

21,0 x 29,7 cm, 10 Seiten

DGLR-Bericht, 1992, 1992-03, DGLR/AIAA 14th Aeroacoustics Conference - Proceedings; S.476-485; 1992; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

aeroacoustics

Bibliothek

1992