Application of amiet’s theory for noise prediction of general airfoil profiles subjected to spanwise-varying inflow conditions

Renato Fuzaro Miotto, William Roberto Wolf, Leandro Dantas De Santana, Cornelis H. Venner

Research output: Chapter in Book/Report/Conference proceedingConference contributionAcademicpeer-review

Abstract

In this paper, three different techniques are combined to provide a complete physics-based semi-anytical model for leading-edge noise prediction. The model is based on the classical theory of Amiet. Here, the two-dimensional turbulence spectrum is computed by a model based on the rapid distortion theory and the aeroacoustic transfer function is numerically evaluated by the boundary element method to account for the effects of the general airfoil profiles. The influence of spanwise inhomogeneities is also considered through the application of the inverse strip method. An assessment of each individual technique on the radiated noise is provided. This research shows that the turbulence distortion occurring at the leadingedge plays a significant role on the predicted noise levels. Compared with the von Kármán model for isotropic turbulence, the rapid distortion theory predicts reduced noise levels at high-frequencies and increased levels at low-frequencies. This paper also shows that the spanwise-varying inflow, here represented by a linearly varying condition, contributes to raising the acoustic radiation when compared to the similar uniform inflow case. By considering modifications on the airfoil leading-edge radius and on the airfoil overall thickness, we show that the leading-edge bluntness plays a key role on reducing gust-airfoil interaction noise. This observation is more pronounced for microphones positioned downstream of the airfoil and for high frequencies.

Original languageEnglish
Title of host publication2018 AIAA/CEAS Aeroacoustics Conference
Place of PublicationReston, Virginia
PublisherAmerican Institute of Aeronautics and Astronautics Inc. (AIAA)
ISBN (Electronic)978-1-62410-560-9
DOIs
Publication statusE-pub ahead of print/First online - 24 Jun 2018
Event24th AIAA/CEAS Aeroacoustics Conference 2018 - Atlanta, United States
Duration: 25 Jun 201829 Jun 2018
Conference number: 24

Conference

Conference24th AIAA/CEAS Aeroacoustics Conference 2018
Abbreviated titleAeroacoustics 2018
CountryUnited States
CityAtlanta
Period25/06/1829/06/18

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Airfoils
Turbulence
Aeroacoustics
Microphones
Boundary element method
Transfer functions
Physics
Acoustics
Radiation

Cite this

Miotto, R. F., Wolf, W. R., De Santana, L. D., & Venner, C. H. (2018). Application of amiet’s theory for noise prediction of general airfoil profiles subjected to spanwise-varying inflow conditions. In 2018 AIAA/CEAS Aeroacoustics Conference [AIAA 2018-3143] Reston, Virginia: American Institute of Aeronautics and Astronautics Inc. (AIAA). https://doi.org/10.2514/6.2018-3143
Miotto, Renato Fuzaro ; Wolf, William Roberto ; De Santana, Leandro Dantas ; Venner, Cornelis H. / Application of amiet’s theory for noise prediction of general airfoil profiles subjected to spanwise-varying inflow conditions. 2018 AIAA/CEAS Aeroacoustics Conference. Reston, Virginia : American Institute of Aeronautics and Astronautics Inc. (AIAA), 2018.
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Miotto, RF, Wolf, WR, De Santana, LD & Venner, CH 2018, Application of amiet’s theory for noise prediction of general airfoil profiles subjected to spanwise-varying inflow conditions. in 2018 AIAA/CEAS Aeroacoustics Conference., AIAA 2018-3143, American Institute of Aeronautics and Astronautics Inc. (AIAA), Reston, Virginia, 24th AIAA/CEAS Aeroacoustics Conference 2018, Atlanta, United States, 25/06/18. https://doi.org/10.2514/6.2018-3143

Application of amiet’s theory for noise prediction of general airfoil profiles subjected to spanwise-varying inflow conditions. / Miotto, Renato Fuzaro; Wolf, William Roberto; De Santana, Leandro Dantas; Venner, Cornelis H.

2018 AIAA/CEAS Aeroacoustics Conference. Reston, Virginia : American Institute of Aeronautics and Astronautics Inc. (AIAA), 2018. AIAA 2018-3143.

Research output: Chapter in Book/Report/Conference proceedingConference contributionAcademicpeer-review

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Miotto RF, Wolf WR, De Santana LD, Venner CH. Application of amiet’s theory for noise prediction of general airfoil profiles subjected to spanwise-varying inflow conditions. In 2018 AIAA/CEAS Aeroacoustics Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics Inc. (AIAA). 2018. AIAA 2018-3143 https://doi.org/10.2514/6.2018-3143