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Aeroacoustics of vehicles is becoming an important design criterion as it directly affects passenger’s comfort. The wind noise at highway speeds (>80 KMPH) is a critical quality concern under normal and crosswind conditions and dominant factor in assessing acoustic comfort of the vehicle. Wind noise is caused by the vortex air flow around a vehicle body and air leakage through the sealing gaps of attached parts. This majorly contributes to high frequency noise (>250 Hz). Accurate identification and control of noise sources and leakage paths result in improved acoustic comfort of the vehicle. In this paper, aero-acoustic quality characteristics of validation prototype vehicle are studied. The major wind noise sources and leakage paths in the vehicle are identified through in-house blower set up in the semi anechoic room. The overall wind noise level and articulation index of vehicle at various speeds are determined through on- road measurements.

As automobiles become increasingly quieter, the wiper operation noise becomes more noticeable by the customer. This paper deals with the experimental approach and the methodology to investigate the Friction induced wiping noise. Role of design in a wiper system plays a very imperative task in meeting the performance of wipers but at the same time it does not cater to the NVH issues. Some of the important design parameters which affect the NVH properties of the wiper system are highlighted in this paper. For better understanding of the system some of the best in class vehicles for SUV category were tested and compared with our test vehicle. In this study more importance given to analytical part which is more important to investigate and in depth study of the friction induced noise. For analytical study some techniques such as time frequency domain i.e. Wavelet transforms, frequency domain and time domain where extensively used.

In today's automobile market, fuel economy is a powerful parameter which gives an edge over competition. Light weight materials play a major role in achieving this. Mirrors tend to underperform in terms of NVH when they are considered for weight optimization. Being light in weight mirrors get easily excited as the energy gets transferred through the structures causing vibration due to their poor damping characteristics. Mirror vibration is a grave concern which affects the vehicle safety. Blur is an effect of vibration which has higher energy levels in vertical and longitudinal direction. It resembles resonance, wherein the vision is zero at certain engine rpm. This paper depicts the approach for mirror blur elimination in the vehicle (prosper segment vehicles), which consider cost as the primary concern. Since the vehicle was nearing SOP design changes was not possible. Certain parameters were attempted without affecting the design as explained in this paper.