Archives of Acoustics, 45, 2, pp. 359–365, 2020

Experimental Study on the Half Flat Tip Serrated Trailing Edge for Stand Fan

Hsiao Mun LEE
Guangzhou University

Kian Meng LIM
National University of Singapore

Jinlong XIE
Guangzhou University

Heow Pueh LEE
National University of Singapore

The effectiveness of half flat tip serrations on reducing fan blade trailing edge noise was investigated using experimental methods. The experiments were conducted at an anechoic chamber under different rotating fan speeds. Numerical simulations were performed to investigate the mass flow rate generated by the serrated fan and compared with that by the baseline fan. The experimental results showed that the overall amount of noise reduction decreased with the increasing of the distance away from the fan. It was found that the effectiveness of the serrations was not proportional with the rotating speed of the fan where it was most effective at 263 rpm and 2041 rpm with noise reductions about 3.1 dBA and 3.5 dBA, respectively. This phenomenon might be depended on how trailing edge vortex would interact with the serrations at different speeds of the fan. The reduction of mass flow rate reduced with the increasing of the rotating speed and the highest reduction was found at 263 rpm which was about 18% and this reduction was accompanied by overall noise reduction of 3.1 dBA.
Keywords: trailing edge noise; half flat tip; serration; stand fan
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Arce-Leon C.A. (2010), Modelling of serrated trailing edges to reduce aerodynamic noise in wind turbine, PhD thesis, Uppsala Universitet, Sweden.

Arce-Leon C. et al. (2017), Effect of trailing edge serration-flow misalignment on airfoil noise emissions, Journal of Sound and Vibration, 405: 19–33, doi: 10.1016/j.jsv.2017.05.035.

Avallone F., Probsting S., Ragni D. (2016), Three-dimensional flow field over a trailing-edge serration and implications on broadband noise, Physics of Fluids, 28(11): 117101 (20 pp.), doi: 10.1063/1.4966633.

Avallone F., Van Der Velden W.C.P., Ragni D., Casalino D. (2018), Noise reduction mechanisms of sawtooth and combed-sawtooth trailing-edge serrations, Journal of Fluid Mechanics, 848: 560–591, doi: 10.1017/jfm.2018.377.

Barone M.F. (2011), Survey of techniques for reduction of wind turbine blade trailing edge noise, Sandia National Laboratories.

Chong T.P., Dubois E. (2016), Optimization of the poro-serrated trailing edges for airfoil broadband noise reduction, The Journal of the Acoustical Society of America, 140(2): 1361–1373, doi: 10.1121/1.4961362.

Chong T.P., Vathylakis A. (2015a), On the aeroacoustic and flow structures developed on a flat plate with a serrated sawtooth trailing edge, Journal of Sound and Vibration, 354: 65–90, doi: 10.1016/j.jsv.2015.05.019.

Chong T.P., Vathylakis A. (2015b), Poro-serrated trailing-edge devices for airfoil self-noise reduction, AIAA Journal, 53(11): 3379–3394, doi: 10.2514/1.J053983.

Geiger D.H. (2004), Comparative analysis of serrated trailing edge designs on idealized aircraft engine fan blades for noise reduction, Virginia Polytechnic Institute and State University.

Howe M.S. (1991), Aerodynamic noise of a serrated trailing edge, Journal of Fluids and Structures, 5(1): 33–45, doi: 10.1016/0889-9746(91)80010-B.

Jaron R., Moreau A., Guerin S., Schnell R. (2018), Optimization of trailing-edge serrations to reduce open-rotor tonal interaction noise, Journal of Fluids Engineering, 140(2): 021201 (12 pp.), doi: 10.1115/1.4037981.

Lee H.M., Lim K.M., Lee H.P. (2018), Reduction of ceiling fan noise by serrated trailing edge, Fluctuation and Noise Letters, 17(3): 1850026 (11 pp.), doi: 10.1142/S0219477518500268.

Liang G.Q., Wang J.C., Chen Y., Zhou C.H., Liang J., Ren L.Q. (2010), The study of owl’s silent flight and noise reduction on fan vane with bionic structure, Advances in Natural Science, 3(2): 192–198, doi: 10.3968/j.ans.1715787020100302.022.

Moreau D.J., Doolan C.J. (2013), Noise-reduction mechanism of a flat-plate serrated trailing edge, AIAA Journal, 51(10): 2513–2522, doi: 10.2514/1.J052436.

Nies J.M., Gageik M.A., Klioutchnikov I., Olivier H. (2015), Investigation of wave phenomena on a blunt airfoil with straight and serrated trailing edges, Experiments in Fluids, 56(7): 136 (14 pp.), doi: 10.1007/s00348-015-2009-4.

Oerlemans S., Schepers J.G. (2009), Prediction of wind turbine noise and validation against experiment, International Journal of Aeroacoustics, 8(6): 555–884, doi: 10.1260/147547209789141489.

Oerlemans S., Sijtsma P., Mendez Lopez B. (2007), Location and quantification of noise sources on a wind turbine, Journal of Sound and Vibration, 299(4–5): 869–883, doi: 10.1016/j.jsv.2006.07.032.

Ryi J., Choi J. (2017), Estimation method to achieve a noise reduction effect of airfoil with a serrated trailing edge for wind turbine rotor, Noise Control Engineering Journal, 65(4): 345–355, doi: 10.3397/1/376550.

DOI: 10.24425/aoa.2020.133156