Leading-Edge Noise Prediction of General Airfoil Profiles with Spanwise-Varying Inflow Conditions

Renato Fuzaro Miotto, William Roberto Wolf, Leandro Dantas De Santana (Corresponding Author)

Research output: Contribution to journalArticleAcademicpeer-review

3 Citations (Scopus)
42 Downloads (Pure)

Abstract

This paper presents a study of the leading-edge noise radiated by an airfoil undergoing a turbulent inflow. The noise prediction of generic airfoil profiles subjected to spanwise-varying inflow conditions is performed with the support of Amiet’s theory and the inverse strip technique. In the proposed methodology, the aeroacoustic transfer function of a generic airfoil profile is computed by the boundary element method. The effects of the airfoil leading-edge thickness on the inflow turbulence are accounted for by a turbulence spectrum based on the rapid distortion theory. This research shows that the turbulence distortion 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 noise levels at low frequencies. This paper also shows that the spanwise-varying inflow, here represented by a linearly changing condition, contributes to raising the noise levels when compared to the similar uniform inflow case. This research confirms that the finite airfoil thickness decreases the airfoil-gust lift response, consequently reducing the noise levels. This observation is more pronounced for microphones positioned downstream of the airfoil and for high frequencies.


Original languageEnglish
Pages (from-to)1711-1716
Number of pages6
JournalAIAA journal
Volume56
Issue number5
Early online date15 Mar 2018
DOIs
Publication statusPublished - May 2018

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Airfoils
Turbulence
Aeroacoustics
Microphones
Boundary element method
Transfer functions

Cite this

Miotto, Renato Fuzaro ; Wolf, William Roberto ; De Santana, Leandro Dantas. / Leading-Edge Noise Prediction of General Airfoil Profiles with Spanwise-Varying Inflow Conditions. In: AIAA journal. 2018 ; Vol. 56, No. 5. pp. 1711-1716.
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abstract = "This paper presents a study of the leading-edge noise radiated by an airfoil undergoing a turbulent inflow. The noise prediction of generic airfoil profiles subjected to spanwise-varying inflow conditions is performed with the support of Amiet’s theory and the inverse strip technique. In the proposed methodology, the aeroacoustic transfer function of a generic airfoil profile is computed by the boundary element method. The effects of the airfoil leading-edge thickness on the inflow turbulence are accounted for by a turbulence spectrum based on the rapid distortion theory. This research shows that the turbulence distortion plays a significant role on the predicted noise levels. Compared with the von K{\'a}rm{\'a}n model for isotropic turbulence, the rapid distortion theory predicts reduced noise levels at high frequencies and increased noise levels at low frequencies. This paper also shows that the spanwise-varying inflow, here represented by a linearly changing condition, contributes to raising the noise levels when compared to the similar uniform inflow case. This research confirms that the finite airfoil thickness decreases the airfoil-gust lift response, consequently reducing the noise levels. This observation is more pronounced for microphones positioned downstream of the airfoil and for high frequencies.",
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Leading-Edge Noise Prediction of General Airfoil Profiles with Spanwise-Varying Inflow Conditions. / Miotto, Renato Fuzaro; Wolf, William Roberto; De Santana, Leandro Dantas (Corresponding Author).

In: AIAA journal, Vol. 56, No. 5, 05.2018, p. 1711-1716.

Research output: Contribution to journalArticleAcademicpeer-review

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