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Methodology to Study the Impact of the Exhaust System on the Vehicle Interior Noise - Identification and Target Setting
Technical Paper
2016-01-1826
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
The transfer characteristics, location of the mounting points, where the exhaust system is attached to the vehicle structure, and the level of excitation forces have a significant contribution to the overall interior noise. The aim of this study is to define targets for the excitation forces of the exhaust line in order to identify its contribution to the overall vehicle interior cabin noise in the early vehicle concept phase when the hardware is not yet available. Furthermore, psychoacoustic parameters are calculated, e.g. the articulation index which provide a representation of the human hearing perception. Therefore a software tool was developed in MATLAB to cascade the interior noise contributions of the exhaust system using the corresponding transfer paths. This tool enables a quick prediction of different combinations (different hanger stiffness and other parameters) to evaluate the potential for improvements. The method combines measured or calculated (FEA) transfer path sensitivity with hanger forces measurements of a similar predecessor exhaust system. To predict the interior noise contributions, the “Mount Stiffness” method is applied in a MATLAB program with a focus on easy use. As the interior noise is a composition of structural noise and tailpipe orifice noise, the predicted noise contribution has been expanded by taking into account the tailpipe noise as well. Moreover, it is possible to import excitation forces directly from CAE codes. The validation has been carried out by recalculating the entire NVH transfer paths and comparing it to noise measurements for different passenger ear positions in a test vehicle.
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Citation
Gartz, R., Rammoser, D., and Maunder, M., "Methodology to Study the Impact of the Exhaust System on the Vehicle Interior Noise - Identification and Target Setting," SAE Technical Paper 2016-01-1826, 2016, https://doi.org/10.4271/2016-01-1826.Also In
References
- Biermayer , W. , Brandl , F. , Hoeldrich , R. , Sontacci , A. et al. 318 Sound Engineering based on Source Contributions and Transfer Path Results JSAE Annual Congress by AVL List GmbH 2007
- Mori , T. , Takaoka , A. , and Maunder , M. Achieving a Vehicle Level Sound Quality Target by a Cascade to System Level Noise and Vibration Targets SAE Technical Paper 2005-01-2394 2005 10.4271/2005-01-2394
- Croker , M. , Maunder , M. , Imai , Y. , Sannodo , N. et al. Reducing Crank Rumble Using Transfer Path Analysis to Assess Engine Modifications SAE Technical Paper 2003-01-1428 2003 10.4271/2003-01-1428
- Van der Seijs , M. General framework for transfer path analysis: History, theory and classification of techniques Mechanical Systems and Signal Processing 2015 10.1016/j.ymssp.2015.08.004
- Webster , J.C. Updating and interpreting the speech interference level (SIL) 1970 Journal of the Audio Engineering Society 18 2
- Unbehaun , M. Exhaust Muffler Shell Noise & Structural Exhaust System Vibration Prediction due to Gas Pulsations in a 2.0l 4Cyl DI Diesel Engine - Jaguar Land Rover 2015 India Software User Conference of Ricardo
- Finger , K. , Brandes , M. , and Schmidt , E. TPA and NVH Prognosis - Application to Mercedes Benz Car Development of New Hybrid Methods Coupling Digital Simulation with Prototype Testing Results SAE Int. J. Passeng. Cars - Mech. Syst. 5 3 1091 1100 2012 10.4271/2012-01-1535