Hostname: page-component-8448b6f56d-wq2xx Total loading time: 0 Render date: 2024-04-24T23:10:53.168Z Has data issue: false hasContentIssue false
  • English
  • Français

Acoustic theory of the many-bladed contra-rotating propeller: the event line and the precession of the interaction source

Published online by Cambridge University Press:  23 December 2020

A.B. Parry Open the ORCID record for A.B. Parry [Opens in a new window]  and
M.J. Kingan Open the ORCID record for M.J. Kingan [Opens in a new window]
A.B. Parry*
Affiliation:
30 Ypres Road, Allestree, DerbyDE22 2LZ, UK
M.J. Kingan
Affiliation:
Department of Mechanical Engineering, University of Auckland, Auckland1010, New Zealand
*
†Email address for correspondence: anthony.parry.pig@gmail.com
Get access Rights & Permissions [Opens in a new window]

Abstract

In the asymptotic theory of interaction noise from contra-rotating propellers with many blades, previous work in the frequency domain has shown that, for each combination mode/tone, the critical points that dominate the acoustic radiation can be linked to two criteria (sonic and normal-edge) and to a radial event line that spins around the annulus at the same speed as the mode. Thus the speed is different for each combination tone. In real time, however, the interactions precess around the annulus at a single speed, governed by the ‘firing order’ of the interactions, with that speed being (in general) considerably different from that of either the front or rear blade rows. The precession of the interaction is described here in detail and then demonstrated by application to three relevant architectures, including a rotor–stator configuration. The paper then considers how the blade leading-edge design affects the radial variation in the interaction location and analyses the interactions from the viewpoint of a far-field observer. The paper also connects previous time- and frequency-domain results by showing that the sonic and normal-edge criteria can be derived in the time domain using the precession speed. The case of equal blade numbers is also included, for which the precession speed becomes infinite but for which, nonetheless, the sonic and normal-edge criteria still apply.

JFM classification

Wakes/Jets: Wakes Acoustics: Aeroacoustics
Type
JFM Rapids
Information
Journal of Fluid Mechanics , Volume 909 , 25 February 2021 , R1
Check for updates
Copyright
© The Author(s), 2020. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Amiet, R.K. 1988 Thickness noise of a propeller and its relation to blade sweep. J. Fluid Mech. 192, 535–560.CrossRefGoogle Scholar
Crighton, D.G. & Parry, A.B. 1991 Asymptotic theory of propeller noise II: supersonic single-rotation propeller. AIAA J. 29, 2031–2037.CrossRefGoogle Scholar
Crighton, D.G. & Parry, A.B. 1992 Higher approximations in the asymptotic theory of propeller noise. AIAA J. 30, 3023–3039.CrossRefGoogle Scholar
Envia, E. 2015 Aeroacoustic analysis of a high-speed open rotor. Intl J. Aeroacoust. 14 (3 and 4), 569–606.CrossRefGoogle Scholar
Hanson, D.B. 1983 Helicoidal surface theory for propeller aerodynamics and noise. AIAA J. 21, 881–889.CrossRefGoogle Scholar
Hanson, D.B. 1985 Noise of counter-rotation propellers. J. Aircraft 22, 609–617.CrossRefGoogle Scholar
Kingan, M.J. & Parry, A.B. 2019 Acoustic theory of the many-bladed contra-rotating propeller: analysis of the effects of blade sweep on wake interaction noise. J. Fluid Mech. 868, 385–427.CrossRefGoogle Scholar
Kingan, M.J. & Parry, A.B. 2020 a Acoustic theory of the many-bladed contra-rotating propeller: the effects of sweep on noise enhancement and reduction. J. Sound Vib. 468, 115089.CrossRefGoogle Scholar
Kingan, M.J. & Parry, A.B. 2020 b Time domain analysis of contra-rotating propeller noise: wake interaction with a downstream propeller blade. J. Fluid Mech. 901, A21.CrossRefGoogle Scholar
Parry, A.B. 1988 Theoretical prediction of counter-rotating propeller noise. PhD thesis, Department of Applied Mathematical Studies, University of Leeds.CrossRefGoogle Scholar
Parry, A.B. 1995 The effect of blade sweep on the reduction and enhancement of supersonic propeller noise. J. Fluid Mech. 293, 181–206.CrossRefGoogle Scholar
Parry, A.B. 1997 Modular prediction scheme for blade row interaction noise. J. Propul. Power 13, 334–341.CrossRefGoogle Scholar
Parry, A.B. & Crighton, D.G. 1986 Theoretical prediction of single-rotation propeller noise. In 10th AIAA Aeroacoustics Conference, Seattle, WA, Jul 9-11. AIAA Paper 86-1891.Google Scholar
Parry, A.B. & Crighton, D.G. 1989 a Asymptotic theory of propeller noise. I – subsonic single-rotation propeller. AIAA J. 27, 1184–1190.CrossRefGoogle Scholar
Parry, A.B. & Crighton, D.G. 1989 b Prediction of counter-rotation propeller noise. In 12th AIAA Aeroacoustics Conference, San Antonio, TX, Apr 10-12. AIAA Paper 89-1141.Google Scholar
Parry, A.B. & Kingan, M.J. 2019 Acoustic theory of the many-bladed contra-rotating propeller: physics of the wake interaction noise critical sources. J. Fluid Mech. 880, 385–427.CrossRefGoogle Scholar
Tyler, J.M. & Sofrin, T.G. 1962 Axial flow compressor noise studies. SAE Trans. 70, 309–332.Google Scholar