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On hydrodynamic and acoustic modes in a ducted shear flow with wall lining

Published online by Cambridge University Press:  04 July 2007

GREGORY G. VILENSKI
Affiliation:
Department of Mathematics and Computer Science, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands
SJOERD W. RIENSTRA
Affiliation:
Department of Mathematics and Computer Science, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands

Abstract

The propagation of small-amplitude modes in an inviscid but sheared subsonic mean flow inside a duct is considered. For isentropic flow in a circular duct with zero swirl and constant mean flow density the pressure modes are described in terms of the eigenvalue problem for the Pridmore-Brown equation with Myers' locally reacting impedance boundary conditions.

The key purpose of the paper is to extend the results of the numerical study of the spectrum for the case of lined ducts with uniform mean flow in Rienstra (Wave Motion, vol. 37, 2003b, p. 119), in order to examine the effects of the shear and wall lining. In the present paper this far more difficult situation is dealt with analytically. The high-frequency short-wavelength asymptotic solution of the problem based on the WKB method is derived for the acoustic part of the spectrum. Owing to the stiffness of the governing equations, an accurate numerical study of the spectral properties of the problem for mean flows with strong shear proves to be a non-trivial task which deserves separate consideration.

The second objective of the paper is to gain theoretical insight into the properties of the hydrodynamic part of the spectrum. An analysis of hydrodynamic modes both in the short-wavelength limit and for the case of the narrow duct is presented. For simplicity, only the hard-wall flow configuration is considered.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

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References

REFERENCES

Barantsev, R. G. & Engelgart, V. N. 1987 Asymptotic Methods in Gas and Fluid Dynamics, pp. 3340. Leningrad University Press (in Russian).Google Scholar
Brambley, E. J. & Peake, N. 2006 Surface-waves, stability, and scattering for a lined duct with flow. Aiaa Paper 2006–2688.Google Scholar
Chapman, C. J. 1994 Sound radiation from a cylindrical duct. Part 1. Ray structure of the duct modes and the external field. J. Fluid Mech. 281, 293311.CrossRefGoogle Scholar
Chapman, C. J. 1996 Sound radiation from a cylindrical duct. Part 2. Source modelling, nil-shielding directions, and the open-to-ducted transfer function. J. Fluid Mech. 313, 367380.Google Scholar
Cooper, A. J. & Peake, N. 2001 Propagation of unsteady disturbances in slowly varying duct with swirling mean flow. J. Fluid Mech. 445, 207234.Google Scholar
Cooper, A. J. & Peake, N. 2005 Upstream-radiated rotor-stator interaction noise in mean swirling flow. J. Fluid Mech. 532, 219250.Google Scholar
Criminale, W. O., Jackson, T. L. & Josine, R. O. 2003 Theory And Computation of Hydrodynamic Stability. Cambridge University Press.CrossRefGoogle Scholar
Drazin, P. G. & Reid, W. H. 2004 Hydrodynamic Stability, 2nd edn. Cambridge University.CrossRefGoogle Scholar
Envia, E. 1998 A high frequency model of cascade noise. AIAA Paper 98–2318.CrossRefGoogle Scholar
Eversman, W. 1991 Theoretical model for duct acoustic propagation and radiation. In Aeroacoustics of Flight Vehicles: Theory and Practice. Volume 2: Noise Control (ed. H. H. Hubbard), Chapter 13, pp. 101–163.Google Scholar
Golubev, V. V. & Atassi, H. M. 1998 Acoustic vorticity waves in swirling flows. J. Sound Vib. 209 (2), 203222.CrossRefGoogle Scholar
Ingard, K. U. 1959 Influence of fluid motion past a plane boundary on sound reflection, absorption and transmission. J. Acoust. Soc. Am. 31 (7), 10351036.CrossRefGoogle Scholar
Keller, J. B. 1985 Semi-classical mechanics. SIAM Rev. 27 (4), 485504.Google Scholar
Korn, G. A. & Korn, T. A. 1968 Mathematical Handbook for Scientists And Engineers. Definitions, Theorems And Formulas For Reference And Review (Second Enlarged And Revised Edn.). McGraw-Hill.Google Scholar
Kousen, K. A. 1999 Eigenmodes of ducted flows with radially-dependent axial and swirl velocity components. NASA/CR–1999–208881.Google Scholar
Lees, L. & Lin, C. C. 1946 Investigation of The Stability of The Laminar Boundary Layer in A Compressible Fluid. NACA Tech. Note. 1115.Google Scholar
Mattheij, R. M. M., Rienstra, S. W. & tenThije Boonkkamp, J. H. M. Thije Boonkkamp, J. H. M. 2005 Partial Differential Equations: Modeling, Analysis, Computation. SIAM, Philadelphia.Google Scholar
Myers, M. K. 1980 On the acoustic boundary condition in the presence of flow. J. Sound Vib. 71 (3), 429434.Google Scholar
Naimark, M. A. 1969 Linear Differential Operators. Nauka, Moscow.Google Scholar
Nijboer, R. 2001 Eigenvalues and eigenfunctions of ducted swirling flows. AIAA Paper 2001–2178.CrossRefGoogle Scholar
Ostashev, V. E. 1997 Acoustics in Moving Inhomogeneous Media. E & FN Spon.Google Scholar
Ovenden, N. C. 2005 A uniformly valid multiple scales solution for cut-on cut-off transition of sound in flow ducts. J. Sound Vib. 286, 403416.CrossRefGoogle Scholar
Ovenden, N. C. & Rienstra, S. W. 2004 Mode-matching strategies in slowly varying engine ducts. AIAA J. 42, 18321840.Google Scholar
Pridmore-Brown, D. C. 1958 Sound Propagation in a fluid flowing through an attenuating duct. Journal of Fluid Mech. 4, 393406.Google Scholar
Rienstra, S. W. 1999 Sound transmission in slowly varying circular and annular lined ducts with flow. J. Fluid Mech. 380, 279296.Google Scholar
Rienstra, S. W. 2003a Sound propagation in slowly varying lined flow ducts of arbitrary cross-section. J. Fluid Mech. 495, 157173.CrossRefGoogle Scholar
Rienstra, S. W. 2003b A classification of duct modes based on surface waves. Wave Motion 37, 119135.Google Scholar
Rienstra, S. W. 2006 Impedance models in time domain, including the extended Helmholtz resonator model. 12th AIAA/CEAS Aeroacoustics Conference, AIAA Paper 2006–2686.Google Scholar
Rienstra, S. W. & Tester, B. T. 2005 An analytic Green's function for a lined circular duct containing uniform mean flow. AIAA Paper 2005–3020. Revised version submitted to J. Sound Vib.CrossRefGoogle Scholar
Schlichting, H., Gersten, K., Krause, E., Oertel, H. & Mayers, K. 2000 Boundary-Layer Theory. Springer.Google Scholar
Smirnov, V. I. 1981 A Course of Higher Mathematics, Volume IV. Nuaka, Moscow (in Russian).Google Scholar
Stakgold, I. 1998 Green's Functions And Boundary Value Problems. Wiley-Interscience.Google Scholar
Tam, C. K. W. & Auriault, L. 1998 The wave modes in ducted swirling flows. J. Fluid Mech. 371, 120.Google Scholar
Vilenski, G. G. 2006 Mode matching in engine ducts with vortical flows. AIAA Paper 2006–2584.Google Scholar
Vilenski, G. G., Rienstra, S. W. 2006 Numerical study of acoustic modes in ducted shear flows. J. Sound Vib. (Submitted).Google Scholar
Zorumski, W. E. 1974 Acoustic theory of axisymmetric multi-sectioned ducts. NASA TR R-419.Google Scholar