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Cross-wavelet analysis of wall pressure fluctuations beneath incompressible turbulent boundary layers

Published online by Cambridge University Press:  25 December 2008

R. CAMUSSI
Affiliation:
Dipartimento di Ingegneria Meccanica e Industriale, Universitá Roma Tre, Via della Vasca Navale 79, 00146 Roma, Italy
G. ROBERT
Affiliation:
Centre Acoustique du LMFA, UMR CNRS 5509, Ecole Centrale de Lyon, Université Claude-Bernard Lyon I, F-69134 Ecully Cedex, France
M. C. JACOB
Affiliation:
Centre Acoustique du LMFA, UMR CNRS 5509, Ecole Centrale de Lyon, Université Claude-Bernard Lyon I, F-69134 Ecully Cedex, France

Abstract

Pressure fluctuations measured at the wall of a turbulent boundary layer are analysed using a bi-variate continuous wavelet transform. Cross-wavelet analyses of pressure signals obtained from microphone pairs are performed and a novel post-processing technique aimed at selecting events with strong local-in-time coherence is applied. Probability density functions and conditionally averaged equivalents of Fourier spectral quantities, usually introduced for modelling purposes, are computed. The analysis is conducted for signals obtained at low Mach numbers from two different non-equilibrium turbulent boundary layer experiments. It is found that that the selected events, though statistically independent, exhibit bi-modal statistics while the conditional coherence function coincides with its non-conditional Fourier equivalent. The physical nature of the selected events has been further explored by the computation of ensemble-averaged pressure time signatures and the results have been physically interpreted with the aid of numerical and experimental results from the literature. In both experiments, it has been found that the major physical mechanisms responsible for the observed conditional statistics are represented by sweep-type events which can be ascribed to the effect of streamwise vortices in the near-wall region. More precisely, the wavelet analysis highlights the convection of the selected structures in both cases. Conversely, compressibilty effects could be related to these events only in one case.

Type
Papers
Copyright
Copyright © Cambridge University Press 2008

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References

REFERENCES

Ahn, B.-K., Graham, W. R. & Rizzi, S. A. 2004 Modelling unsteady wall pressures beneath turbulent boundary layers. NASA-AIAA 2004-2849.CrossRefGoogle Scholar
Bendat, J. S. & Piersol, A. G. 2000 Random Data: Analysis and Measurements Procedures, 3rd ed.Wiley.Google Scholar
Blake, W. K. 1986 Mechanics of Flow Induced Sound and Vibrations. Academic.Google Scholar
Bradshaw, P. 1967 Inactive motion and pressure fluctuations in turbulent boundary layers. J. Fluid Mech. 30, 241258.Google Scholar
Brungart, T. A., Lauchle, G. C., Deutsch, S. & Riggs, E. T. 2002 Wall pressure fluctuations induced by separated/reattached channel flow. J. Sound Vib. 251, 558577.CrossRefGoogle Scholar
Bull, M. K. 1996 Wall pressure fluctuations beneath turbulent layer: some reflections on forty years of research. J. Sound Vib. 190, 299315.CrossRefGoogle Scholar
Camussi, R. & Guj, G. 1997 Orthonormal wavelet decomposition of turbulent flows: intermittency and coherent structures. J. Fluid Mech. 348, 177199.CrossRefGoogle Scholar
Camussi, R., Guj, G., Barbagallo, D. & Prischich, D. 2000 Experimental characterization of the aeroacoustic behaviour of a low speed wind tunnel. AIAA Paper 2000–1986.Google Scholar
Camussi, R. & Di Felice, F. 2006 Statistical properties of large scale spanwise structures in zero pressure gradient turbulent boundary layers. Phys. Fluids 18, 035108.CrossRefGoogle Scholar
Camussi, R., Guj, G., Di Marco, A. & Ragni, A. 2006 a Propagation of wall pressure perturbations in a large aspect-ratio shallow cavity. Exps. Fluids 40, 612620.CrossRefGoogle Scholar
Camussi, R, Guj, G. & Ragni, A. 2006 b Wall pressure fluctuations induced by turbulent boundary layers over surface discontinuities. J. Sound Vib. 294, 177204.Google Scholar
Chainais, P., Abry, P. & Pinton, J. F. 1999 Intermittency and coherent structures in a turbulent flow: a wavelet analysis of joint pressure and velocity measurements. Phys. Fluids 11, 35243539.CrossRefGoogle Scholar
Chase, D. M. 1980 Modeling the wave-vector frequency spectrum of turbulent boundary layer wall pressure. J. Sound Vib. 70, 2968.CrossRefGoogle Scholar
Corcos, G. M. 1963 a The structure of the turbulent pressure field in boundary-layer flows. J. Fluid Mech. 18, 353378.CrossRefGoogle Scholar
Corcos, G. M. 1963 b Resolution of pressures in turbulence. J. Acous. Soc. Am. 35, 192199.CrossRefGoogle Scholar
Daubechies, I. 1992 Ten Lectures on Wavelet. CBMS-NSF Reg. Conf. Ser. Appl. Maths.CrossRefGoogle Scholar
Dhanak, M. R. & Dowling, A. P. 1995 On the pressure fluctuations induced by coherent vortex motion near a surface. AIAA Paper 95-2240.Google Scholar
Dhanak, M. R., Dowling, A. P. & Si, C. 1997 Coherent vortex model for surface pressure fluctuations induced by the wall region of a turbulent boundary layer. Phys. Fluids 9, 27162731.Google Scholar
Efimtsov, B. M. 1986 Vibrations of a cylindrical panel in a field of turbulent pressure fluctuations. Sov. Phys. Acoust. 32, 336337.Google Scholar
Farabee, T. M. & Casarella, M. J. 1991 Spectral features of wall pressure fluctuations beneath turbulent boundary layers. Phys. Fluids A 3, 24102420.CrossRefGoogle Scholar
Farge, M. 1992 Wavelet transforms and their applications to turbulence. Annu. Rev. Fluid Mech. 24, 395457.CrossRefGoogle Scholar
Feller, W. 1968 An Introduction to Probability Theory and Its Applications, 3rd edn.Wiley.Google Scholar
Goupillaud, P., Grossmann, A. & Morlet, J. 1984 Cycle-octave and related transforms in seismic signal analysis. Geoexploration 23, 85102.Google Scholar
Graham, W. R. 1997 A comparison of models for the wavenumber-frequency spectrum of turbulent boundary layer pressures. J. Sound Vib. 206, 541565.CrossRefGoogle Scholar
Grinsted, A., Moore, J. C. & Jevrejeva, S. 2004 Application of the cross wavelet transform and wavelet coherence to geophysical time series. Non Lin. Proc. Geophys. 11, 561566.Google Scholar
Guj, G. & Camussi, R. 1999 Statistical analysis of local turbulent energy fluctuations, J. Fluid Mech. 382, 126.CrossRefGoogle Scholar
Hudgins, L., Friebe, C. & Mayer, M. 1993 Wavelet transforms and atmospheric turbulence. Phys. Rev. Lett. 71, 32793282.CrossRefGoogle Scholar
Jayasundera, S., Casarella, M. & Russel, S. 1996 Identification of coherent motions using wall pressure signatures. Tech. Rep. 19960918-036, Catholic Univ. of America, Washington DC. (available at http://handle.dtic.mil/100.2/ADA314537).Google Scholar
Jevrejeva, S., Moore, J. C. & Grinsted, A. 2003 Influence of the arctic oscillation and El Nino-Southern Oscillation (ENSO) on ice conditions in the Baltic Sea: The wavelet approach. J. Geophys. Res. 108, 46774681.Google Scholar
Johansson, A. V., Her, J.-Y. & Haritonidis, J. H. 1987 On the generation of high-amplitude wall-pressure peaks in turbulent boundary layers and spots. J. Fluid Mech. 175, 119142.CrossRefGoogle Scholar
Kim, J. 1989 On the structure of pressure fluctuations in simulated turbulent channel flow. J. Fluid Mech. 205, 421451.Google Scholar
Kim, J., Choi, J. & Sung, H. J. 2002 Relationship between wall pressure fluctuations and streamwise vortices in a turbulent boundary layer. Phys. Fluids A 14, 898901.CrossRefGoogle Scholar
Lamballais, E., Lesieur, M. & Metais, O. 1997 Probability distribution functions and coherent structures in a turbulent channel. Phys. Rev. E 56, 67616766.Google Scholar
Lee, I. & Sung, H. J. 2002 Multiple-arrayed pressure measurement for investigation of the unsteady flow structure of a reattaching shear layer. J. Fluid Mech. 463, 377402.CrossRefGoogle Scholar
Li, H. 1998 Identification of coherent structures in turbulent shear flow with wavelet correlation analysis. Trans. ASME: J. Fluids Engng 120, 778785.Google Scholar
Mallat, S. 1989 A theory for multiresolution signal decomposition: the wavelet representation. IEEE Trans. PAMI 11, 674693.CrossRefGoogle Scholar
Maraun, D. & Kurths, J. 2004 Cross wavelet analysis: significance testing and pitfalls. Non lin. Proc. Geophys. 11, 505514.Google Scholar
Onorato, M., Salvetti, M. V., Buresti, G. & Petagna, P. 1997 Application of a wavelet cross-correlation analysis to DNS velocity signals. Eur. J. Mech. B/Fluids 16, 575597.Google Scholar
Orlandi, P. & Jimenez, J. 1994 On the generation of turbulent wall friction. Phys. Fluids 6, 634641.Google Scholar
Perry, A. E. & Chong, M. S. 1982 On the mechanism of wall turbulence. J. Fluid Mech. 119, 173217.Google Scholar
Poggie, J. & Smiths, A. J. 1997 Wavelet analysis of wall-pressure fluctuations in a supersonic blunt fin flow. AIAA J. 35, 15971603.Google Scholar
Robert, G. 2002 Experimental data base for the pressure gradient effect. Rep. 3.2.1. UE Research Programme, Contract No. G4RD-CT-2000-00223.Google Scholar
Schewe, G. 1983 On the structure and the resolution of wall pressure fluctuations associated with turbulent boundary-layer flow. J. Fluid Mech. 134, 311328.CrossRefGoogle Scholar
Smol'yakov, A. V. & Tkachenko, V. M. 1991 Model of a field of pseudosonic turbulent wall pressures and experimental data. Sov. Phys. Acoust. 37, 627631.Google Scholar
Torrence, C. & Compo, G. P. 1998 Apractical guide to wavelet analysis. Bull Am. Met. Soc. 79, 6178.2.0.CO;2>CrossRefGoogle Scholar
Torrence, C. & Webster, P. J. 1999 Interdecadal changes in the ENSOMonsoon system. J. Climate 12, 26792690.2.0.CO;2>CrossRefGoogle Scholar