Pass by Noise Reduction on a Medium Commercial Tipper Vehicle

With the current developments in emission and safety norms in the Indian motor vehicle segment, there is always a challenge for engineers to design the components without hampering the existing performance of the vehicle and meet the legal requirements of the market. The challenge is to reach the optimum point of iterative modifications where the overall vehicle efficacy is increased. The Pass by noise (PBN) target is one such parameter that need to be assured to certify new vehicles/variants for their Noise emissions. PBN requirements are an important aspect of NVH development of a vehicle. The vehicles running on the Indian roads must comply with the PBN requirements defined by standard IS: 3028.

Tipper is a vehicle used in mainly mining areas and on hilly terrains having high gear ratios and thereby producing more noise. This paper discuss the approach used to reduce the noise in this worst case. The hardware changes done in this worst case vehicle can be universally adopted in other vehicles also, having higher empty weights and lower overall gear ratios. Hence re-development for pass by noise in other vehicles can be avoided.