Identification of Some Acoustic Noise Sources in Cars by Speckle Interferometry
Acoustic noise reduction is an important subject of research and development efforts for car manufacturers. Some of the most important sources of noise are investigated by different techniques, mostly acoustical, like acoustical holography. Tires and their interaction with the road and with the surrounding car structures are one of these noise sources. So does the motor and the associated components. The conditions in which the noise is produced are extremely varied. Some of the parameters involved are speed, road properties, tire model and pressure, developped power, environment, brakes, different mechanical and acoustical properties of assemblyes, individual components, outer panels of the car body, and so on.