The largest amount of transportation around the world is done using cars. In addition to considering the advantages of automobiles for transportation there is much adverse effect of automobiles on the surrounding environment as well as on human health. Transport accounts for between 20% and 25% of total greenhouse gas emissions in industrialised countries. Transport noise is one of the main sources of noise pollution that also causes discomfort during the night. The document describes noise and vibration in automobiles, their sources, methods of control and their effect.
Studio noise and vibration is a very important task in front of the acoustic engineer while designing and manufacturing any vehicle. Sound is a type of energy propagation that travels with a particular velocity through a medium. When a sound wave crosses its particular limit it becomes an unwanted sound and the unwanted sound is known as noise. Vibration is variation or displacement of the body with respect to the specific reference position over time. The vibration is the oscillation that is usually felt rather than heard. Within a vehicle many components contribute to the total emitted noise and vibration of the vehicle. Treatment from a single source will not affect total radiated noise. In order to achieve overall noise reduction for the car, all sources of noise and their path of transfer to the radiant component have to be treated simultaneously and in a holistic approach.