Browse Publications Technical Papers 2001-01-1558
2001-04-30

Frame Resonance of High Air Flow Resistivity Plastic Foams: Properties to Improve Acoustical Absorption of Composite Multi-Layered Systems 2001-01-1558

The optimization of acoustical properties of multi-layered materials used in the automotive industry requires a good understanding and characterization of the various component layers. This is a particular concern in the case of headliners where performance must be balanced with packing space demands. These composite structures when used with flexible urethane foams provide good stiffness and light weight, but their acoustic performance can be sub-optimal. Measurements undertaken with poro-elastic high airflow resistivity foams highlighted frame resonances which, if exploited, might significantly improve the acoustical performance of this system.
A new modeling technique based on a pseudo-macroscopic description of the poro-elastic material in the framework of a four-pole network will be used to explain these frame resonances. This formulation exploits the electro-acoustical analogy in transmission line theory. The description of the poro-elastic material is based on a global description of the structure superposed on the fluid. Under normal incidence, each phase is assumed to support a compressional wave. In the present study, emphasis will be put on tools to tune these systems to a specific range of frequency and comparison of predictions and measurements will be presented to assess the validity of the modeling technique.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Preview Document Add to Cart
Members save up to 17% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Design of a New Bumper Beam Using Structural Thermoplastic Composite

930542

View Details

TECHNICAL PAPER

Numerical Analysis of Integrated Glass Antenna Systems

982386

View Details

TECHNICAL PAPER

Full Vehicle NVH CAE Methodology Development to Address Tailgate Rattling on a Future Tata SUV

2019-26-0213

View Details

X