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The automotive industry is one of the industries that have visibility suffered a strong demand for higher environmental performance. This industry have enjoyed years as the main source of employment and economic growth, today it is being pointed out as one of the major contributors to air pollution in urban centers. Indeed the benefits of automobile provide the means of gaining access to life's necessities and employment and a source of pleasure. However, despite these benefits there are environmental burdens as well: local air pollution, greenhouse gas emissions, road congestion, noise, mortality and morbidity from accidents and less open space to roads. Thus companies in the sector have been trying different strategies to overcome these challenges Evaluation of Emission development for commercial vehicles had always been great challenge to continuously migrate from one level of emission norm to other maintaining the business continuity.

In the automotive industry several attributes needs to be considered for the development of a new vehicle which are important for the customer, such as vehicle dynamics, driveability, fuel consumption, emissions, durability and NVH among many others. Sometimes these characteristics are conflicting and often need is to create a robust trade-off where the design space is sufficient to fit all of them in a vehicle that rhymes with the brand image and is appealing to the intended customer. Automobile manufacturers try to meet the requirements with respect to quality and comfort and often, emotional, aspects supercede the previous objective, pragmatic demands. The satisfaction of the demands by the customers concerning comfort, driving pleasure, design appears dominant and functionality criteria sometimes takes a back seat. NVH is considered to be one of the key buy in factor among the above mentioned attributes.

Commercial vehicle NVH attributes primarily focus on interior noise for driver's comfort and exterior noise for environmental legislation. Major sources for both the interior and exterior noise are power train unit, exhaust and air intake system. This paper focuses on development of Air Intake System (AIS) for better interior and exterior NVH performance for medium and heavy commercial vehicles. For air intake system, structural radiations from its panels and nozzle noise are significant contributors on overall vehicle NVH. Noise generation mechanism in air intake system occurs due to opening and closing of the valves and inlet air column oscillation by sharp pressure pulse from cylinder. Based on benchmarking, vehicle level targets have been arrived, and then cascaded to system and sub-system level targets. For air intake system, targets for nozzle noise at wide open throttle condition have been set for exterior NVH performance.