Acoustic Effects of Lightweighting in a Sport Utility Vehicle 2019-01-1506
Recently a vehicle study was performed to determine if the current production sound package in a sport utility vehicle could be improved while reducing or maintaining the weight. The study focused on sound package parts which typically utilize a heavy barrier layer to provide sound transmission loss: carpet, rear wheelhouse inner and trunk insulation, and dash inner. In addition, the heavy-weight underbody shields were replaced with lightweight compressed fiber to allow for increased coverage and to evaluate the effect on additional possible engine noise paths.
Testing was performed both at the component level in the laboratory and at the vehicle level on the road. This paper presents the results of that study.
It was found that the sound levels were improved slightly with the lower-weight parts, while articulation index was greatly improved. This was due to a combination of two factors. The physical properties of the new parts were better optimized to provide sound absorption in the frequency range of interest while still providing the necessary sound transmission loss along the noise paths. The new parts were also made of lighter-weight material, which allowed for increased coverage and therefore more absorption area.
Andrea Lynne Frey
Autoneum North America Inc.
Noise and Vibration Conference & Exhibition