Noise reduction of an airfoil model covered by bio-inspired herringbone riblets

He, Haoxiang1; Bai, Honglei1; Zhang, Shixiong1; Liu, Yu2

2024-10-01

10.1063/5.0226117

PHYSICS OF FLUIDS   影响因子和分区

1070-6631

1089-7666

It is curious that whether the typical herringbone pattern of bird flight feathers plays a role in attenuating aeroacoustic noise. Being motivated by this, experiments are conducted to investigate noise reduction of the NACA0012 (National Advisory Committee for Aeronautics) airfoil-based model with one side surface covered by bio-inspired herringbone patterns of riblets. The herringbone-ribbed surface is defined by the divergent angle beta (= 60 degrees) of the riblets pattern, the spanwise wavelength lambda (= 0.2c and 0.4c) of the pattern, and the riblet height h (= 0.6%c and 1.2%c), where c is the chord length of the airfoil. While far-field sound pressure fluctuations are measured via microphones in an anechoic wind tunnel, flow fields around the model are captured using particle image velocimetry (PIV) in a water tunnel. The effective angle of attack of the test models ranges from alpha(eff) = -11.1 degrees to 11.1 degrees and Reynolds number considered is from Re = 2.3 x 10(5) to 7.8 x 10(5). Compared with the baseline smooth models, the models with the riblet pattern on the pressure side are able to substantially suppress the tonal noise, associated with considerable reduction in the overall noise. The reduction in the overall sound pressure levels of the tonal noise and the overall noise are up to 21.3 dB and 20.5 dB, respectively, at alpha(eff) = -2.2 degrees and Re = 3.6 x 10(5). The noise reduction is attributed to the transition of laminar to turbulent boundary layers over the herringbone-ribbed surface, particularly in the saddle location where the spanwise-repeated herringbone pattern converges. Behavior of shear layers separating from the trailing edge of the model is examined, corroborating the proposition that the acoustic feedback loop is impaired by the herringbone-ribbed surface.

SCI

英语

其他

National Natural Science Foundation of China (NSFC)[12072382] ; null[XFX20220201]

Mechanics ; Physics

Mechanics ; Physics, Fluids & Plasmas

WOS:001326840000011

AIP Publishing

Web of Science

1.Sun Yat Sen Univ, Sch Aeronaut & Astronaut, Shenzhen Campus, Shenzhen 518107, Peoples R China
2.Southern Univ Sci & Technol, Dept Mech & Aerosp Engn, Shenzhen 518055, Peoples R China

He, Haoxiang,Bai, Honglei,Zhang, Shixiong,et al. Noise reduction of an airfoil model covered by bio-inspired herringbone riblets[J]. PHYSICS OF FLUIDS,2024,36(10).

He, Haoxiang,Bai, Honglei,Zhang, Shixiong,&Liu, Yu.(2024).Noise reduction of an airfoil model covered by bio-inspired herringbone riblets.PHYSICS OF FLUIDS,36(10).

He, Haoxiang,et al."Noise reduction of an airfoil model covered by bio-inspired herringbone riblets".PHYSICS OF FLUIDS 36.10(2024).