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Experimental Investigation of Low-Frequency Noise and Vibration in a Bus
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 01, 2020 by SAE International in United States
Annotation ability available
Event: Automotive Technical Papers
The low-frequency noise effects passenger comfort causing headaches, tiredness, and pressure on the eardrum. The mid- and high-frequency noises of an automotive vehicle can be easily attenuated with passive methods. The passive method involves the usage of fibrous or porous acoustic materials for sound absorption. But the reduction of low-frequency noise with passive methods is difficult. Hence the noise must be reduced at the source. The present work is related to the root cause identification of low-frequency noise and vibration in a bus. After the analysis of vehicle interior noise and vibration data acquired in static and dynamic operating conditions, it is identified that 30-40 Hz is the main problematic noise frequency band. From the component vibration data and modal testing results, it is concluded that unbalance in propeller shaft and resonance in the upper berth structure are the sources of this low-frequency noise. This is also confirmed with both acoustic and vibration operating deflection shapes (ODS) analysis carried out at vehicle interior.
CitationSelvaraj, K., Padavala, P., Rajamohan, K., and Medisetti, J., "Experimental Investigation of Low-Frequency Noise and Vibration in a Bus," SAE Technical Paper 2020-01-5082, 2020, https://doi.org/10.4271/2020-01-5082.
- Jawale, P. , and Karanth, N. , “Interior Noise and Vibration Reduction of BRT - Premium Segment Bus,” SAE Technical Paper 2017-01-1866, 2017, https://doi.org/10.4271/2017-01-1866.
- Bijwe, V. , Raut, M. , Suryawanshi, S. , Naidu, S. et al. , “NVH Refinement of Passenger Vehicle for In-cab Boom Noise Using Experimental Operational Deflection Shape and Full Vehicle Acoustic Sensitivity Simulations,” SAE Technical Paper 2011-26-0063, 2011, https://doi.org/10.4271/2011-26-0063.
- Naga Suresh, I. , Sudhakara Naidu, T. , Ambardekar, M. , and Arora, G. , “NVH Improvement of a Bus Through AC Compressor Drive-Ratio Change,” SAE Technical Paper 2009-26-0045, 2009, https://doi.org/10.4271/2009-26-0045.
- Cerrato, G. , and Goodes, P. , “Practical Approaches to Solving Noise and Vibration Problems,” Sound and Vibration 45(4):18, 2011.
- Schwarz, B.J. , and Richardson, M.H. , “Introduction to Operating Deflection Shapes,” CSI Reliability Week 10:121-126, 1999.
- Frank, J. , Doshi, S. , Rao, M. , and Raghavendran, P. , “Reduction of Driveline Boom Noise and Vibration of 40 Seat Bus through Structural Optimization,” SAE Technical Paper 2017-28-1926, 2017, https://doi.org/10.4271/2017-28-1926.
- Wang, C. , Fang, D. , and Guo, F. , "Experimental Study on Source Identification of Bus Floor’s Vibration," SAE Technical Paper 2014-01-0014, 2014, https://doi.org/10.4271/2014-01-0014.