Effect of Damping on Sound Transmission Loss through Automotive Body Panels

2009-01-2202

05/19/2009

Event
SAE 2009 Noise and Vibration Conference and Exhibition
Authors Abstract
Content
In this paper, sound transmission characteristics of typical stamped steel automotive body panels are investigated. In particular, focus was placed on the dash panel since it separates the interior space from the engine. Three dash panels were considered with the same geometry but different damping characteristics. These dash panels included a bare steel dash, a bare steel dash with a Patch Constrained Layer (PCL) and a laminated steel dash. Sound transmission loss was measured in a transmission loss suite. It was observed that the measured transmission loss of the laminated steel dash was significantly higher than the other dash panels throughout the mid and high frequency regions. A hybrid approach using both Finite Element Analysis and Statistical Energy Analysis (SEA) was used to predict and correlate the sound transmission loss for these panels. The geometry effects of the dash panels were considered while calculating SEA parameters. Coupling loss factors between the dash panel and acoustic cavity were predicted considering the effects of increased stiffness and the impedance mismatches due to discontinuities along the surface of the dash. The power contributions to the receiving cavity by resonant paths and non-resonant paths were investigated. It was observed that the resonant power contribution was significantly lower for the laminated steel dash as compared to the other dash panels. This resulted in higher transmission loss for laminated steel dash compared to the transmission loss for other two panels.
Meta TagsDetails
DOI
https://doi.org/10.4271/2009-01-2202
Pages
6
Citation
Patil, A., and Goetchius, G., "Effect of Damping on Sound Transmission Loss through Automotive Body Panels," SAE Technical Paper 2009-01-2202, 2009, https://doi.org/10.4271/2009-01-2202.
Additional Details
Publisher
Published
May 19, 2009
Product Code
2009-01-2202
Content Type
Technical Paper
Language
English