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New Psychoacoustic Criteria for Turbocharger Aero Noise
Technical Paper
2019-01-1489
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
With ever more stringent regulations related to air pollution and CO2 emissions, there is a growing trend to address this through the downsizing of automotive engines. Turbochargers are used to improve engine power by using exhaust gas energy to provide boosted air pressure for better efficiency. They are a key element in powertrains of today and in the future. During real operating conditions, the rotational speed of a turbo varies greatly making this rotating machinery run in “continuous transient” phases and produces unwanted noises as a result. Recently, we identified a new source of aero noise while developing a new type of turbocharger. Our typical in-house procedure for characterizing usual aero broad band noise source was to use the 3-microphone methodology for measuring the acoustic intensity. However, this methodology is not well adapted if the noise source is tonal, not constant over time and includes high frequency content, which is the case with the new type of turbocharger design and which could create bad noise perception in case of noise transfer into the vehicle cabin. As a result and first step, a set of new psychoacoustic criteria was studied to better understand the relationship between the turbocharger design and the noise content characteristics in addition to the existing methodology. Two new metrics called « Fluctuation Standard Deviation Ratio » and « Low Frequency Peak Emergence » were developed to fulfill this need. The “Fluctuation Standard Deviation Ratio” is assessed in the time domain and can be connected to the human perception of a «steam locomotive», which for a usual compressor flow noise can lead to connotations such as “feeling of unsafety”. The low frequency peak emergence is assessed in the frequency domain and relates to a perception of an annoying whistling sound, which is easily captured by human ears when the peak frequency is below 2 kHz - 3 kHz. Both criteria will be detailed in this paper. Their relevance with human perception will also be shown using practical examples.
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Citation
Rigault, A., Kihm, F., and Baron, N., "New Psychoacoustic Criteria for Turbocharger Aero Noise," SAE Technical Paper 2019-01-1489, 2019, https://doi.org/10.4271/2019-01-1489.Also In
References
- Thierry Lefèvre (Honeywell Garrett Engine Boosting System), Lucille Lamotte (MicrodB) The Development of an Objective Rating for Turbocharger Noise Inter-Noise 2003 2003
- Gladys Gaudé (Honeywell Turbo Technologies), Thierry Lefèvre (Honeywell Turbo Technologies), Lucille Lamotte (MicrodB) Improvement of an Objective Rating for Turbocharger Tonal Noise Inter-Noise 2006 2003
- Jang , S.-H. and Jeong-Guon 1997
- Jaimes , I. Sound Intensity Measurements in Turbocharger Compressor Ducts Using Multi-Microphone Arrays Automotive NVH Comfort Le Mans 2016 2016
- Feldbauer , C. and Höldrich , R. Realization of a Vold-Kalman Tracking Filter a Least Squares Problem Conference on Digital Audio Effects (DAFX-00) Verona, Italy 2000
- Tůma , J. Frequency Response of the Vold Order Tracking Filter 2001 Seminar, Instruments and Control Ostrava 2001
- Herlufsen , H. , Gade , S. , and Konstantin-Hansen , H. Characteristics of the Vold/Kalman Order Tracking Filter Sound and Vibration 1999
- Fastl , H. Psychoacoustic Basis of Sound Quality Evaluation and Sound Engineering ICSV13 - Vienna Jul 2006
- Zwicker , E. and Fastl , H. Psycho-Acoustics: Facts and Models Springer Series in Information Sciences 1990
- Alt , N.W. , Wiehagen , N. , and Michael , W. Interior Noise Simulation for Improved Vehicle Sound SAE Technical Paper 2001-01-1539 2001 10.4271/2001-01-1539
- Eisele , G. , Wolff , K. , Alt , N. , and Hüser , M. Application of Vehicle Interior Noise Simulation (VINS) for NVH Analysis of a Passenger Car SAE Technical Paper 2005-01-2514 2005 10.4271/2005-01-2514
- Schuhmacher , A. Techniques for Measuring the Vibro-Acoustic Transfer Function Sound and Vibration 2010