A literature review for the analysis of viboracoustic properties of periodic inclusions in porous materials

The design based on periodic elements is a powerful strategy for the achievement of lightweight sound packages and represents a convenient solution for manufacturing aspects. An interesting research target is the inclusion of vibroacoustic design rules at early stage of products development through the use of porous media with periodic inclusions, which exhibit proper dynamic filtering effects; this offers different applications in transportation (aeronautics, space, automotive, railway), energy and civil engineering sectors, where both weight and space, as well as vibroacoustic integrity and comfort, still remain as critical issues. This work is a literature review which mainly focuses on three aspects concerning periodic inclusions in porous materials: the concept of substitution of a fluid layer for a porous layer, the Transfer Matrix Method and the descriptions of two alternatives to multi-layering.