The prime factors governing the automobile industry today are that of safety, efficiency and above all comfort, a lot of research has gone in to meet the above objectives. NVH is the industry term used to cover the subject of vibration and sounds.Weight reduction of automobiles is necessary in improving fuel efficiency, but this would worsen the noise, vibration and harshness (NVH) characteristics of the vehicles, resulting in bad ride comfort. On the other hand, use of damping materials to improve the NVH characteristics would increase the weight of the vehicles, resulting in poor fuel efficiency. Important noise and vibration sources in automobiles are engine, â€œexterior air flow, road profile, and exhaust noise, power train noise. Among all these, the engine generated considerable noise and vibration in either running or standstill states, hence we can consider the engine one of the most important noise and vibration sources in automobiles.Â The main noise sources in the engine are the combustion noise, fuel injector noise, mechanical noise, inlet and exhaust noise, cooling fan noise from the ancillaries such as the generator or compressor.Â But in all the noise most of them so well attenuated. Hence engineering focus is switching to power train noise, road noise and tyre noise. Power train noise is reduced largely by improvements in engines, transmission â€“ housing and transfer core design, semiconductor technology that could lead to frictionless bearing and the possibilities using energy fields to transmit power verses solid media.Â In the following presentation we have focused on the recent development with the use of up coming material for cabin, have drastically cut down the noise level and also beefed up the fuel economy.
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