NVH Considerations for Highly Asymmetric Laminated Glass in Electric Vehicles

Abstract

<div class="section abstract"><div class="htmlview paragraph">The innovation and application of new technologies in battery electric vehicle (BEV) development continues to be a key objective of the automotive industry. One such area of development is glazing designs that reduce transmission of noise into vehicle interiors. Highly asymmetric laminated front side lites that consist of thick soda lime glass exterior plies laminated with thinner ion exchanged interior plies with acoustic polyvinyl butyral interlayers offer substantially reduced noise transmission compared to industry standard monolithic front side lites. These asymmetric laminate designs also provide additional benefits of improved toughness and penetration resistance. This paper documents a study that uses a systematic test-based approach to understand the sensitivity of interior vehicle noise behavior to changes in acoustic attenuation driven by installation of asymmetric laminated glass front side lites.</div><div class="htmlview paragraph">The test-based assessment included within this study was conducted to isolate the individual contributions and influence of wind, road, and powertrain induced interior noise shares associated with highly asymmetric laminated glass front side lite integration. To facilitate this separation and comparison, a multi-step process was conducted. First, a baseline BEV was characterized including operational, source, and transfer function measurements. This data was utilized to develop a time-domain noise transfer path analysis (TPA) model. Second, asymmetric laminated front side lites were replaced on the baseline EV and corresponding transfer functions were measured. Lastly, the asymmetric laminated glass transfer functions were exchanged in the TPA model to obtain interior noise shares associated with wind, road, and powertrain contributions. Based on the results from this comparison, improvement was observed in vehicle NVH performance using the highly asymmetric glass laminates, relative to conventional monolithic front side lites.</div></div>