Multi-layered noise control systems are widely used in production vehicles to reduce interior noise levels. Traditionally, these systems had fibrous felt cores but increasingly moulded polyurethane (PUR) foam-backed carpets are now used. They provide the manufacturer with a single unit moulded car carpet, enabling easy and cheaper installation. However, little information has been published on their performance characteristics or their design optimization. This paper reports on work that examines the optimization of composite performance of these composites. A design model is developed which allows performance to be assessed before expensive road trials are carried out.
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