Structure Borne Sound Transmission Through a Motor Vehicle

Sound transmission at joints in a motor vehicle is studied using Statistical Energy Analysis. It is shown that transmission at edges of windows can be modelled successfully as transmission past an elastic interlayer. Coupling from the car body to the doors is modelled as transmission across a pin. Corner cross and tee joints between panels are also studied. Measurements were carried out on a motor vehicle using an impulsive noise source and results for acceleration level differences and damping are presented.

The measured results are compared with results obtained using a Statistical Energy Analysis model for sound transmission, where only bending wave transmission is considered. Large acceleration level differences are measured and predicted results show good agreement. The results show that Statistical Energy Analysis techniques can be used to study structure borne sound transmission in motor vehicles.