Vibroacoustics of periodic media: Multi-scale modelling and design of structures with improved vibroacoustic performance

Structural periodic design is a powerful approach to achieve lightweight structures that can be manufactured in a cost-efficient manner. Periodic media exhibit specific dynamic filtering effects that can be used for advanced vibroacoustic design. How periodic concepts can improve the broadband vibroacoustic signature and performance is still an open question to be answered, knowing that the beneficial effects of most of the vibroacoustic treatments are frequency band limited. This Special Issue focuses on these main themes. It connects to the research activities of the VIPER project (Vibroacoustics of Periodic Media) MSCA ITN-EJD grant agreement No 675441; http://viper.ec-lyon.fr). This challenging research field is inherently multi-disciplinary since it requires expertise from material science, vibration and acoustics as well as from applied mathematics. This is reflected in the papers in this Special Issue. It collects novel concepts and techniques that enable to develop and to validate the design of global vibroacoustic treatments based on periodic patterns allowing for passive control of vibration and acoustic paths in layered concepts. Furthermore, they shed some light on future exploration paths. Contributions can be found about the application of concepts of periodicity and quasi-periodicity. They involve both theoretical and numerical approaches as well as validations with experimental measurements. Waveguides in various materials and models are investigated by using both deterministic, stochastic and possibilistic approaches that address and link the meso-scale (representative elementary volume or elementary cell) and macro-scale (full-size structure). Each scale is characterized by its own indicators: effective parameters at the meso-scale (mechanical and acoustical equivalent material properties, dispersion characteristics, poro-elasticity. . .) and vibroacoustic indicators at the macro-scale (structural damping, acoustic absorption, transmission loss. . .). Techniques and approaches that reduce the computational costs of the models and that increase the knowledge gained from combinations of materials and structures represent an added value for vibroacoustic researchers and designers. This Special Issue combines papers issued from the works done in the VIPER project and contributions from the community, that address the various challenging aspects related to the vibroacoustics of periodic structures