Broadband Airfoil Trailing-Edge Noise Prediction from Measured Surface Pressures and Spanwise Length Scales
In this paper an effective approach to estimate airfoil Turbulent Boundary-Layer Trailing-Edge (TBL-TE) far-field noise from measured surface pressure fluctuations (SPF) is evaluated. Measurements of both SPF and TE noise were performed on a NACA 0012 airfoil of 0.4 m chord at Reynolds numbers of 1....
Saved in:
Published in | International journal of aeroacoustics Vol. 12; no. 1-2; pp. 53 - 82 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
London, England
SAGE Publications
01.01.2013
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | In this paper an effective approach to estimate airfoil Turbulent Boundary-Layer
Trailing-Edge (TBL-TE) far-field noise from measured surface pressure fluctuations (SPF)
is evaluated. Measurements of both SPF and TE noise were performed on a NACA 0012 airfoil
of 0.4 m chord at Reynolds numbers of 1.0–1.9 millions for various angles of attack. A
non-homogeneously spaced array of five Kulite-sensors near the TE at
x/c = 0.989 is employed to measure point spectra and
spanwise two-point correlations of surface pressure fluctuations. Finally spanwise SPF
length-scales are derived as function of frequency. Comparisons to measured TE noise and
semi-empirical predictions of surface pressures and far-field noise show very good
agreement. It is found, that the proposed method can cover a larger frequency range than
standard acoustic measurement techniques. Therefore it can provide valuable assistance in
extending spectra obtained conventionally, mainly to low frequencies. Furthermore,
pressure and suction side contributions to far-field noise can be obtained separately. |
---|---|
Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
ISSN: | 1475-472X 2048-4003 |
DOI: | 10.1260/1475-472X.12.1-2.53 |