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Effect of Screens and Pinhole Size on Measured Fluctuating Surface Pressures Using a Micro-Electro-Mechanical Microphone Array
Technical Paper
2017-01-1783
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Surface pressure measurements using microphone arrays are still challenging, especially in an automotive context with cruising speeds around Mach 0.1. The separated turbulent boundary layer excitation and the side mirror wake flow generate both acoustic and aerodynamic components, which have wavenumbers that differ by a factor of approximately 10. This calls for high spatial resolution measurements to fully resolve the wavenumber-frequency spectrum. In a previous publication [1], the authors reported a micro-electro-mechanical (MEMS) surface microphone array that successfully used wavenumber analysis to quantify acoustic versus turbulence loading. It was shown that the measured surface pressure at each microphone could be strongly influenced by self-noise induced by the microphone “packaging”, which can be attenuated with a suitable windscreen. This paper reports the results of wind tunnel tests to more accurately define the sensitivity of the MEMS microphone array with and without windscreens. The tests involved controlled attached boundary layer flow measurements in the anechoic wind tunnel at University of Sherbrooke. Different microphone sensing ports are evaluated as well as different microphone windscreens.
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Todter, C., Robin, O., Bremner, P., Marchetto, C. et al., "Effect of Screens and Pinhole Size on Measured Fluctuating Surface Pressures Using a Micro-Electro-Mechanical Microphone Array," SAE Technical Paper 2017-01-1783, 2017, https://doi.org/10.4271/2017-01-1783.Data Sets - Support Documents
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References
- Bremner , P. , Todter , C. , and Clifton , S. Sideglass Turbulence and Wind Noise Sources Measured with a High Resolution Surface Pressure Array SAE Int. J. Passeng. Cars - Mech. Syst. 8 3 1063 1074 2015 10.4271/2015-01-2325
- Corcos , G. M. Resolution of pressure in turbulence The Journal of the Acoustical Society of America 35 2 192 199 1963
- Lueptow , R. M. Transducer resolution and the turbulent wall pressure spectrum The Journal of the Acoustical Society of America 97 1 370 378 1995
- Lecoq , D. , Pézerat , C. , Chevillotte , F. , and Bessis , R. Measurement of the low-wavenumber component within a turbulent wall pressure by an inverse problem of vibration The Journal of the Acoustical Society of America 140 3 1974 1980 2016
- Krause , J. , Gallman , J. , Moeller , M. , and White , R. D. A Microphone Array on a Chip for High Spatial Resolution Measurements of Turbulence Journal of Microelectromechanical Systems 23 5 1164 1181 2014
- Pearse , J. R. , and Kingan , M. J. Measurement of sound in airflow 13th International Congress on Sound and Vibration Vienna, Austria July 2-6, 2006
- Jaeger , S. , Horne , W. , and Allen , C. Effect of surface treatment on array microphone self-noise 6th Aeroacoustics Conference and Exhibit, Aeroacoustics Conferences Lahaina, USA 2000 10.2514/6.2000-1937
- Fleury , V. , Coste , L. Davy , R. , Mignosi , A. et al. Optimization of microphone array wall mounting in closed-section wind-tunnels AIAA J. 50 11 2325 2335 2012 10.2514/1.J051336
- Szöke M. and Azarpeyvand M. Reduction of the hydrodynamic noise on a beamforming array Berlin Beamforming Conference 2016
- Robin , O. , Moreau , S. , Padois , T. , and Berry , A. Measurement of the wavenumber-frequency spectrum of wall pressure fluctuations: spiral-shaped rotative arrays with pinhole-mounted quarter inch microphones 19th AIAA/CEAS Aeroacoustics Conference, Aeroacoustics Conferences Berlin, Germany 2013 10.2514/6.2013-2058
- Padois , T. , Robin , O. , and Berry , A. 3D Source localization in a closed wind-tunnel using microphone arrays 19th AIAA/CEAS Aeroacoustics Conference, Aeroacoustics Conferences Berlin, Germany 2013 10.2514/6.2013-2213
- Miller , T. , Gallman , J. and Moeller , M. Review of Turbulent Boundary Layer Models for Acoustic Analysis Proc. AIAA Aerospace Sciences Meeting Orlando Jan, 2011
- Capone D. E. , and Lauchle A.G.C. Calculation of turbulent boundary layer wall pressure spectra J. Acoust. Soc. Am. 98 4 2226 2234 1995
- Blake W.K. Mechanics of Flow-Induced Sound and Vibration I and II Academic Press New York 1986
- Goody , M. Empirical Spectral Model of Surface Pressure Fluctuations AIAA Journal 42 9 September 2004