Wind tunnel testing and embedded large eddy simulations are employed to study the noise reduction of trailing-edge finlets
on an airfoil. Trailing-edgefinlets
are shown to increase the distance between the highly energetic fluid particles and the sharp trailingedge. Experiments were conducted at different angles of attack. Wind tunnel measurements confirm that finlets reduce the broadband noise radiated by the
airfoil. Results also reveal that the noise reduction of finlets is dependent on the airfoil angle of attack,
and that the highest noise reduction is obtained at the largest angle of
attack tested.
References
[1]
Ortega, C.P. (2012) Chapter 2: Effects of Noise Pollution on Birds: A Brief Review of Our Knowledge. In: Ornithological Monographs, Vol. 74, American Ornithological Society, USA, 6-22. https://doi.org/10.1525/om.2012.74.1.6
[2]
Bronzaft, A.L. (2004) Noise Pollution: A Threat to Our Mental and Physical Well-Being. The Journal of the Acoustical Society of America, 115, 2567-2567. https://doi.org/10.1121/1.4784049
[3]
Jianu, O., Naterer, G. and Rosen, M. (2011) Noise Pollution Prevention in Wind Turbines: Status and Recent Advances. Proceedings of the 1st World Sustainability Forum (on line), 1-30 November.
[4]
Graham, R.R. (1934) The Silent Flight of Owls. The Journal of the Royal Aeronautical Society, 38, 837-843. https://doi.org/10.1017/S0368393100109915
[5]
Lilley, G. (1998) A Study of the Silent Flight of the Owl. 4th AIAA/CEAS Aeroacoustics Conference, Toulouse, 2-4 June 1998, AIAA 98-2340. https://doi.org/10.2514/6.1998-2340
[6]
Clark, I.A., Alexander, W.N., Devenport, W., Glegg, S., Jaworski, J.W., Daly, C. and Peake, N. (2017) Bioinspired Trailing-Edge Noise Control. AIAA Journal, 55, 740-754. https://doi.org/10.2514/1.J055243
[7]
Afshari, A., Azarpeyvand, M., Dehghan, A.A. and Szoke, M. (2017) Effects of Streamwise Surface Treatments on Trailing Edge Noise Reduction. 23rd AIAA/CEAS Aeroacoustics Conference, Denver, 5-9 June 2017, AIAA 2017-3499. https://doi.org/10.2514/6.2017-3499
[8]
Manoha, E., Troff, B. and Sagaut, P. (2000) Trailing-Edge Noise Prediction Using Large-Eddy Simulation and Acoustic Analogy. AIAA Journal, 38, 575-583. https://doi.org/10.2514/2.1015
[9]
Agrawal, B.R. and Sharma, A. (2016) Numerical Investigations of Bio-Inspired Blade Designs to Reduce Broadband Noise in Aircraft Engines and Wind Turbines. 54th AIAA Aerospace Sciences Meeting, San Diego, 4-8 January 2016, AIAA 2016-0760. https://doi.org/10.2514/6.2016-0760
[10]
Tang, H., Lei, Y. and Fu, Y. (2019) Noise Reduction Mechanisms of an Airfoil with Trailing Edge Serrations at Low Mach Number. Applied Sciences, 9, 3784. https://doi.org/10.3390/app9183784
[11]
Zilstra, A. and Johnson, D. (2019) LES and FW-H Prediction of Aeroacoustic Noise for a SD 7037 Airfoil for Wind Turbine Applications. 25th AIAA/CEAS Aeroacoustics Conference, Delft, 20-23 May 2019, AIAA 2019-2537. https://doi.org/10.2514/6.2019-2537
[12]
Bodling, A. and Sharma, A. (2018) Numerical Investigation of Low-Noise Airfoils Inspired by the Down Coat of Owls. Bioinspiration & Biomimetics, 14, Article ID: 016013. https://doi.org/10.2514/6.2018-3925
[13]
Rumpfkeil, M.P. (2017) Using Steady Flow Analysis for Noise Predictions. Computers & Fluids, 154, 347-357. https://doi.org/10.1016/j.compfluid.2017.03.003
[14]
Quéméré, P. and Sagaut, P. (2002) Zonal Multi-Domain RANS/LES Simulations of Turbulent Flows. International Journal for Numerical Methods in Fluids, 40, 903-925. https://doi.org/10.1002/fld.381
[15]
Terracol, M. (2006) A Zonal RANS/LES Approach for Noise Sources Prediction. Flow, Turbulence and Combustion, 77, 161-184. https://doi.org/10.1007/s10494-006-9042-6
[16]
Fröhlich, J. and von Terzi, D. (2008) Hybrid LES/RANS Methods for the Simulation of Turbulent Flows. Progress in Aerospace Sciences, 44, 349-377. https://doi.org/10.1016/j.paerosci.2008.05.001
[17]
Kim, T., Jeon, M., Lee, S. and Shin, H. (2014) Numerical Simulation of Flatback Airfoil Aerodynamic Noise. Renewable Energy, 65, 192-201. https://doi.org/10.1016/j.renene.2013.08.036
[18]
Lane, G., Croaker, P. and Ding, Y. (2019) Embedded Large Eddy Simulation Method for Predicting Flow-Induced Noise. Proceedings of ACOUSTICS, Cape Schanck, 10-13 November 2019, 1-10.
[19]
Zuo, Z.G., Huang, Q. and Liu, S. (2019) An Analysis on the Flow Field Structures and the Aerodynamic Noise of Airfoils with Serrated Trailing Edges Based on Embedded Large Eddy Flow Simulations. Journal of Applied Fluid Mechanics, 12, 327-339. https://doi.org/10.29252/jafm.12.02.29142
[20]
ANSYS (2019) Fluent 2019 Theory Guide. ANSYS, Inc., Canonsburg.
[21]
Leonard, A. (1975) Energy Cascade in Large-Eddy Simulations of Turbulent Fluid Flows. Advances in Geophysics, 18, 237-248. https://doi.org/10.1016/S0065-2687(08)60464-1
[22]
Hinze, J.O. (1987) Turbulence. McGraw-Hill, New York.
[23]
Nicoud, F. and Ducros, F. (1999) Subgrid-Scale Stress Modelling Based on the Square of the Velocity Gradient Tensor. Flow, Turbulence and Combustion, 62, 183-200. https://doi.org/10.1023/A:1009995426001
[24]
Hughes, R.L. (2007) A Mathematical Determination of von Karman’s Constant, Κ. Journal of Hydraulic Research, 45, 563-566. https://doi.org/10.1080/00221686.2007.9521792
[25]
Bailey, S.C.C., et al. (2014) Estimating the Value of von Kármán’s Constant in Turbulent Pipe Flow. Journal of Fluid Mechanics, 749, 79-98. https://doi.org/10.1017/jfm.2014.208
[26]
Liu, Z., Wu, Y. and Li, B. (2020) An Assessment on the Performance of Sub-Grid Scale Models of Large Eddy Simulation in Modeling Bubbly Flows. Powder Technology, 374, 470-481. https://doi.org/10.1016/j.powtec.2020.07.055
[27]
Mathey, F., Cokljat, D., Bertoglio, J.P. and Sergent, E. (2006) Assessment of the Vortex Method for Large Eddy Simulation Inlet Conditions. Progress in Computational Fluid Dynamics, 6, 58-67. https://doi.org/10.1504/PCFD.2006.009483
[28]
Lighthill, M.J. (1952) On Sound Generated Aerodynamically. Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, 211, 564-587. https://doi.org/10.1098/rspa.1952.0060
[29]
Ffowcs-Williams, J.E. and Hawkings, D.L. (1969) Sound Generation by Turbulence and Surfaces in Arbitrary Motion. Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, 264, 321-342. https://doi.org/10.1098/rsta.1969.0031
[30]
Brentner, K.S. and Farassat, F. (1998) Analytical Comparison of the Acoustic Analogy and Kirchhoff Formulation for Moving Surfaces. AIAA Journal, 36, 1379-1386. https://doi.org/10.2514/2.558
[31]
Shi, Y.J. and Lee, S. (2020) Numerical Study of 3-D Finlets Using Reynolds-Averaged Navier-Stokes Computational Fluid Dynamics for Trailing Edge Noise Reduction. International Journal of Aeroacoustics, 19, 95-118. https://doi.org/10.1177/1475472X20905053
[32]
Berger, M. and Aftosmis, M. (2012) Progress towards a Cartesian Cut-Cell Method for Viscous Compressible Flow. 50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition, Nashville, 9-12 January 2012, AIAA 2012-1301. https://doi.org/10.2514/6.2012-1301
[33]
Ghmati, R.E., Ali Jawad, B. and Koutsavdis, E. (2012) An Investigation of CutCell Meshing Strategies for Accurate Aerodynamic Performance Prediction. SAE International Journal of Passenger Cars-Mechanical Systems, 5, 369-380. https://doi.org/10.4271/2012-01-0499
[34]
Menter, F.R. (2012) Best Practice: Scale-Resolving Simulations in ANSYS CFD. ANSYS Germany GmbH, Darmstadt, 1.
[35]
ANSYS (2019) Fluent 2019 User Guide. ANSYS, Inc., Canonsburg.
Menter, F.R. (2015) Best Practice: Scale-Resolving Simulations in ANSYS CFD. ANSYS Germany GmbH, Darmstadt.
[38]
Al Tlua, B. and Rocha, J. (2019) Development and Testing of an Aeroacoustic Wind Tunnel Test Section. Canadian Acoustics, 47, 64-65.
[39]
Al Tlua, B. and Rocha, J. (2020) Optimization and Testing of Flat-Plate Trailing-Edge Serration Geometry for Reducing Airfoil Self-Noise. Canadian Acoustics, 48, 7-17.
[40]
Clauser, F.H. (1954) Turbulent Boundary Layers in Adverse Pressure Gradients. Journal of the Aeronautical Sciences, 21, 91-108. https://doi.org/10.2514/8.2938
[41]
Falkner, V.M. and Skan, W. (1930) Some Approximate Solutions of the Boundary Layer Equations. A.R.C Reports and Memoranda, No. 1314.
[42]
Lee, H. and Kang, S.H. (2000) Flow Characteristics of Transitional Boundary Layers on an Airfoil in Wakes. Journal of Fluids Engineering, 122, 522-532. https://doi.org/10.1115/1.1287592
[43]
Marsden, O., Bogey, C. and Bailly, C. (2006) Direct Noise Computation around a 3-D NACA 0012 Airfoil. 12th AIAA/CEAS Aeroacoustics Conference (27th AIAA Aeroacoustics Conference), Cambridge, 8-10 May 2006, AIAA 2006-2503. https://doi.org/10.2514/6.2006-2503
[44]
Chong, M.S., Perry, A.E. and Cantwell, B.J. (1990) A General Classification of Three-Dimensional Flow Fields. Physics of Fluids A: Fluid Dynamics, 2, 765-777. https://doi.org/10.1063/1.857730
[45]
Amiet, R.K. (1976) Noise Due to Turbulent Flow past a Trailing Edge. Journal of Sound and Vibration, 47, 387-393. https://doi.org/10.1016/0022-460X(76)90948-2
[46]
Williams, J.E.F. and Hall, L.H. (1970) Aerodynamic Sound Generation by Turbulent Flow in the Vicinity of a Scattering Half Plane. Journal of Fluid Mechanics, 40, 657-670. https://doi.org/10.1017/S0022112070000368
[47]
Press, W.H., Flannery, B.P., Teukolsky, S.A. and Vetterling, W.T. (1986) Numerical Recipes. Cambridge University Press, Cambridge.
[48]
Gstrein, F., Zang, N. and Azarpeyvand, M. (2020) Application of Finlets for Trailing Edge Noise Reduction of a NACA 0012 Airfoil. AIAA Aviation 2020 Forum (virtual event), 15-19 June 2020, AIAA 2020-2502. https://doi.org/10.2514/6.2020-2502
