Interior Floor Engineering: Acoustic vs. Compression Performance

The interior floor of a vehicle cabin occupies a significant amount of surface area in proportion to the cabin as a whole, and as such provides a prime opportunity for acoustic treatment. Generally speaking, floor materials must be relatively limp to achieve high acoustic performance. However, the tactile quality of a vehicle floor is very important. The end customer has an expectation for how it should feel to step onto the floor of a vehicle: a carpet should “give” slightly, but not compress fully, under pressure. A carpet that is too stiff or not stiff enough may be perceived as indicative of low quality. Thus, acoustic targets and stiffness targets tend to be at odds. A vehicle interior floor is a trim component which consists of different layers and which can have different pile-up configurations. Such a pile-up typically consists of a soft layer, called a decoupler, and a top layer. Previous work has shown how CAE tools can predict part-level compression behavior during design and work in conjunction with established tools for NVH performance prediction. This paper will examine the acoustic effects of compression behavior of floor materials as installed in the vehicle by means of several vehicle-level acoustic tests, both static and dynamic.