Acoustic Modeling for Three-Dimensional Lightweight Automotive Windshields

Paper #:
  • 2018-01-0141

  • 2018-04-03
In the auto industry, lightweight glass designs are drawing more attention for enabling improved gas mileage and reduced exhaust emission. Windshield hybrid laminates using Corning® Gorilla® Glass for Automotive Glazing enable more than 30% weight reduction compared to conventional soda-lime glass laminates. In addition, Gorilla hybrid laminates also showed significantly improved toughness due to advanced ion-exchange technology that provides high surface compression compared to conventional soda-lime glass laminates. Regardless of these benefits, the reduced mass also allows for increased transmission of sound waves through such windshields into the vehicle cabin. A system-level measurement approach has always been employed to assess overall vehicle acoustic performance by measuring sound pressure levels (SPL) at the driver’s ears. The measured sound signals are usually a superimposition of a variety of noise sources and transmission paths. As a result, it is challenging to quantitatively isolate the impact of replacing a thick windshield with a thin windshield. A reverberation room measurement is another standard component-level testing approach that can be used to evaluate the impact of replacing a thick windshield with a thin windshield, but this approach is usually limited to flat glass evaluation. To enhance the understanding of sound wave transmission through windshields, a 3D windshield acoustic model was developed using ANSYS Acoustics ACT. The model was first validated for a 24” x 24” flat laminated panel with reverberation data. It was then extended for simulating a 3D production windshield with curved surface and tri-layer PVB lamination. The model was employed to characterize windshield acoustic performance under either plane wave incidence or diffuse field. Through modeling simulation, it was found that shape of the windshield has important impact on both critical frequency and sound transmission loss (STL) distribution. For a wrap-around windshield design, the critical frequency shifted to a lower value due to increased bending stiffness compared to the standard one. In such windshields, the STL was improved by 1-5 dB at frequencies above 4,100Hz while being degraded at lower frequencies. In addition, the wave incident direction was also analyzed to study its impact on sound transmission loss and corresponding glass deformation pattern.
SAE MOBILUS Subscriber? You may already have access.
Attention: This item is not yet published. Pre-Order to be notified, via email, when it becomes available.
Members save up to 36% off list price.
HTML for Linking to Page
Page URL

Related Items

Technical Paper / Journal Article
Technical Paper / Journal Article
Technical Paper / Journal Article