Acoustic study of novel eco-friendly material for vehicle NVH applications

Abstract A new environmentally friendly sound absorbing material designed for vehicle noise absorption and insulation applications is presented and its acoustic properties are studied in this paper. First the general physical properties of the relatively light and soft material are introduced. Scanning electronic microscope (SEM) imaging results are provided to expose the internal structure of the material with fibrous nature, composed of reticulated natural leather collagen based foam. The principal part of the paper presents a complete acoustic study of the novel material and describes adequate methods to experimentally determine the main acoustic properties of this type of materials. Measurement procedures are followed by analysis of characteristics and results obtained from the experiments. Finally the acoustic effect of the material is validated by the applicational tests, fitted inside motorcycle helmets. The results of the acoustic study demonstrate the appropriateness of the material for a variety of vehicle NVH implementations were noise absorption and transmission insulation are required.