Investigation and Validation of Transmission Loss for Vehicle Components with a Large Aperture

Determination of the sound transmission loss (STL) of a vehicle component that has a large aperture, such as an air exhauster or an air extraction opening, always presents a challenge to an acoustics engineer. The complexity of the aperture's physical conditions cannot be easily solved with conventional, analytical or numerical methods. A systematic study of investigating the transmission loss characteristics of the large aperture is presented in this paper. Both conventional potential noise reduction predictions of large apertures and SEA simulations were performed. Transmission losses with different acoustic treatments were measured and predicted when using AutoSEA2. Finally, correlation between measured results and predications were developed. The ultimate goal of this study is to reduce the costly transmission loss measurements with correlated analytical estimations