Enhanced sound transmission loss of a truss-like cellular structure in broad-band low frequency domains

The low frequency sound transmission loss (STL) behavior of cellular truss-like auxetic structures is investigated. For this purpose, cellular truss-like auxetic structures are used as the core of sandwich panels and the two-dimensional in-plane STL of the sandwich structures are calculated using validated FE simulations. Significant superiority of the STL behavior in terms of high bandwidth at low frequency domain (1-1000 Hz) is observed compared with other cellular materials. The results of parametric studies demonstrate strong effects of geometric parameters on the STL of the structure and could allow for fine-tuning of the acoustic properties.