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Experimental investigation of aerofoil tonal noise generation

Published online by Cambridge University Press:  23 April 2014

S. Pröbsting ,
J. Serpieri  and
F. Scarano
S. Pröbsting*
Affiliation:
Department of Aerospace Engineering, Delft University of Technology, Delft, 2629 HS, The Netherlands
J. Serpieri
Affiliation:
Department of Aerospace Engineering, Delft University of Technology, Delft, 2629 HS, The Netherlands Department of Industrial Engineering, University of Naples Federico II, Naples, 80125, Italy
F. Scarano
Affiliation:
Department of Aerospace Engineering, Delft University of Technology, Delft, 2629 HS, The Netherlands
*
†Email address for correspondence: [email protected]
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Abstract

The present study investigates the mechanisms associated with tonal noise emission from a NACA 0012 aerofoil at moderate incidence ($0^{\circ },1^{\circ },2^{\circ }$ and $4^{\circ }$ angle of attack) and with Reynolds numbers ranging from 100 000 to 270 000. Simultaneous time-resolved particle image velocimetry (PIV) of the aeroacoustic source region near the trailing edge and acoustic measurements in the far field are performed in order to establish the correspondence between the flow structure and acoustic emissions. Results of these experiments are presented and analysed in view of past research for a number of selected cases. Characteristics of the acoustic emission and principal features of the average flow field agree with data presented in previous studies on the topic. Time-resolved analysis shows that downstream convecting vortical structures, resulting from growing shear layer instabilities, coherently pass the trailing edge at a frequency equal to that of the dominant tone. Therefore, the scattering of the vortical structures and their associated wall pressure fluctuations are identified as tone generating mechanisms for the cases investigated here. Moreover, wavelet analysis of the acoustic pressure and velocity signals near the trailing edge show a similar periodic amplitude modulation which is associated with multiple tonal peaks in the acoustic spectrum. Periodic amplitude modulation of the acoustic pressure and velocity fluctuations on the pressure side are also observed when transition is forced on the suction side, showing that pressure-side events alone can be the cause.

JFM classification

Acoustics: Aeroacoustics Boundary Layers: Boundary layer stability Vortex Flows: Vortex shedding
Type
Papers
Information
Journal of Fluid Mechanics , Volume 747 , 25 May 2014 , pp. 656 - 687
Copyright
© 2014 Cambridge University Press 

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References

Aizin, L. 1992 Sound generation by a Tollmien–Schlichting wave at the end of a plate in a flow. J. Appl. Mech. Tech. Phys. 3, 50–57.Google Scholar
Amiet, R. 1976 Noise due to turbulent flow past a trailing edge. J. Sound Vib. 47 (3), 387–393.CrossRefGoogle Scholar
Arbey, H. & Bataille, J. 1983 Noise generated by airfoil profiles placed in a uniform laminar flow. J. Fluid Mech. 134, 33–47.CrossRefGoogle Scholar
Arcondoulis, E. J. G., Doolan, C. J., Zander, A. C. & Brooks, L. A. 2010 A review of trailing edge noise generated by airfoils at low to moderate Reynolds number. Acoust. Austral. 38 (3), 387–393.Google Scholar
Atobe, T., Tuinstra, M. & Takagi, S. 2009 Airfoil tonal noise generation in resonant environments. Trans. Japan. Soc. Aeronaut. Space Sci. 52 (176), 74–80.CrossRefGoogle Scholar
Boutilier, M. S. H. & Yarusevych, S. 2012 Separated shear layer transition over an airfoil at a low Reynolds number. Phys. Fluids 24, 084105.CrossRefGoogle Scholar
Brooks, T. F. & Hodgson, T. H. 1981 Trailing edge noise prediction from measured surface pressures. J. Sound Vib. 78 (1), 69–117.CrossRefGoogle Scholar
Brooks, T. F., Pope, D. S. & Marcolini, M. A.1989 Airfoil self-noise and prediction. NASA Tech. Rep. 1218. Reference Publication.Google Scholar
Chong, T. P. & Joseph, P. F. 2012 Ladder structure in tonal noise generated by laminar flow around an airfoil. J. Acoust. Soc. Am. 131 (6), EL461–EL467.CrossRefGoogle ScholarPubMed
Desquesnes, G., Terracol, M. & Sagaut, P. 2007 Numerical investigation of the tone noise mechanism over laminar airfoils. J. Fluid Mech. 591, 155–182.CrossRefGoogle Scholar
Fink, M. R. 1975 Prediction of airfoil tone frequencies. J. Aircraft 12, 118–120.CrossRefGoogle Scholar
Harris, F. J. 1978 On then use of windows for harmonic analysis with the Fourier transform. Proc. IEEE 66 (1), 51–83.CrossRefGoogle Scholar
Henning, A., Kaepernick, K., Ehrenfried, K., Koop, L. & Dillmann, A. 2008 Investigation of aeroacoustic noise generation by simultaneous particle image velocimetry and microphone measurements. Exp. Fluids 45, 1073–1085.CrossRefGoogle Scholar
Hersh, A. S. & Hayden, R. E.1971 Aerodynamic sound radiation from lifting surfaces with and without leading-edge serrations. NASA Tech. Rep. 114370. Contr. Rep.Google Scholar
Howe, M. S. 1978 A review of the theory of trailing edge noise. J. Sound Vib. 61 (3), 437–465.CrossRefGoogle Scholar
Hutcheson, F. V. & Brooks, T. F.2002 Measurement of trailing edge noise using directional array and coherent output power methods. In Eighth AIAA/CEAS Aeroacoustics Conf. Breckenridge, Colorado.CrossRefGoogle Scholar
Ikeda, T., Atobe, T. & Takagi, S. 2012 Direct simulations of trailing-edge noise generation from two-dimensional airfoils at low Reynolds numbers. J. Sound Vib. 331 (3), 556–574.CrossRefGoogle Scholar
van Ingen, J. & Kotsonis, M.2011 A two-parameter method for $\mathrm{e}^{N}$ transition prediction. In Sixth AIAA Theoretical Fluid Mechanics Conf. Honolulu, Hawaii, vol. AIAA 2011-3928.Google Scholar
Jones, L. E. & Sandberg, R. D. 2011 Numerical analysis of tonal airfoil self-noise and acoustic feedback-loops. J. Sound Vib. 330, 6137–6152.CrossRefGoogle Scholar
Kingan, M. J. & Pearse, J. R. 2009 Laminar boundary layer instability noise produced by an aerofoil. J. Sound Vib. 322, 808–828.CrossRefGoogle Scholar
Lowson, M. V., Fiddes, S. P. & Nash, E. C.1994 Laminar boundary layer aeroacoustic instabilities. AIAA Paper (94-0358).CrossRefGoogle Scholar
Lowson, M. V., McAlpine, A. & Nash, E. C.1998 The generation of boundary layer instability noise on aerofoils. AIAA Paper (98-0626).CrossRefGoogle Scholar
McAlpine, A., Nash, E. C. & Lowson, M. V. 1999 On the generation of discrete frequency tones by the flow around an aerofoil. J. Sound Vib. 222 (5), 753–779.CrossRefGoogle Scholar
Morris, S. C. 2011 Shear-layer instabilities: particle image velocimetry measurements and implications for acoustics. Annu. Rev. Fluid Mech. 43 (1), 529–550.CrossRefGoogle Scholar
Nakano, T., Fujisawa, N. & Lee, S. 2006 Measurement of tonal-noise characteristics and periodic flow structure around NACA 0018 airfoil. Exp. Fluids 40, 482–490.CrossRefGoogle Scholar
Nash, E. C., Lowson, M. V. & McAlpine, A. 1999 Boundary layer instability noise on airfoils. J. Fluid Mech. 382, 27–61.CrossRefGoogle Scholar
Paterson, R. W., Vogt, P., Fink, M. R. & Munch, C. 1973 Vortex noise of isolated airfoils. J. Aircraft 10 (5), 296–302.CrossRefGoogle Scholar
Plogmann, B., Herrig, A. & Würz, W. 2013 Experimental investigations of a trailing edge noise feedback mechanism on a NACA 0012 airfoil. Exp. Fluids 54, 1480.CrossRefGoogle Scholar
Raffel, M., Willert, C. E., Wereley, S. T. & Kompenhans, J. 2007 Particle Image Velocimetry. A Practical Guide. 2nd edn Springer.CrossRefGoogle Scholar
Roger, M. & Moreau, S. 2010 Extensions and limitations of analytical airfoil broadband noise models. Intl J. Aeroacoust. 9 (3), 273–305.CrossRefGoogle Scholar
Sandberg, R. D. & Jones, L. E. 2011 Direct numerical simulations of low Reynolds number flow over airfoils with trailing edge serrations. J. Sound Vib. 330, 3818–3831.CrossRefGoogle Scholar
Sandberg, R. D., Jones, L. E., Sandham, N. D. & Joseph, P. F. 2009 Direct numerical simulations of tonal noise generated by laminar flow past airfoils. J. Sound Vib. 320, 838–858.CrossRefGoogle Scholar
Scarano, F. 2003 Theory of non-isotropic spatial resolution in PIV. Exp. Fluids 35, 268–277.CrossRefGoogle Scholar
Schröder, A., Herr, M., Lauke, T. & Dierksheide, U. 2006 A study on trailing edge noise sources using high-speed particle image velocimetry. In New Results in Numerical and Experimental Fluid Mechanics V (ed. Rath, H. J., Holze, C., Heinemann, H.-J., Henke, R. & Hönlinger, H.), pp. 373–380. Springer.CrossRefGoogle Scholar
Shannon, D. & Morris, S. C. 2006 Experimental investigation of a blunt trailing edge flow field with application to sound generation. Exp. Fluids 41 (5), 777–788.CrossRefGoogle Scholar
Takagi, S. & Konishi, Y. 2010 Frequency selection mechanism of airfoil trailing-edge noise. J. Aircraft 47 (4), 1111–1116.CrossRefGoogle Scholar
Tam, C. K. W. 1974 Discrete tones of isolated airfoils. J. Acoust. Soc. Am. 55 (6), 1173–1177.CrossRefGoogle Scholar
Tam, C. K. W. & Ju, H. 2012 Aerofoil tones at moderate Reynolds number. J. Fluid Mech. 690, 536–570.CrossRefGoogle Scholar
Torrence, C. & Compo, G. 1998 A practical guide to wavelet analysis. Bull. Am. Meteorol. Soc.2.0.CO;2>CrossRefGoogle Scholar
Welch, P. D. 1967 The use of fast Fourier transform for the estimation of power spectra: a method based on time averaging over short, modified periodograms. IEEE Trans. Audio Electroacoust. 15, 70–73.CrossRefGoogle Scholar
Wright, S. E. 1976 The acoustic spectrum of axial flow machines. J. Sound Vib. 45 (2), 165–223.CrossRefGoogle Scholar

Pröbsting et al. supplementary movie

Sequence of velocity vectors and contours of spanwise vorticity component, case 1.

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