In recent years, boundary element method (BEM) and ﬁnite element method (FEM) implementations of acoustics in ﬂuids with viscous and thermal losses have been developed. They are based on the linearized Navier–Stokes equations with no ﬂow. In this paper, such models with acoustic losses are applied to an acoustic metamaterial. Metamaterials are structures formed by smaller, usually periodic, units showing remarkable physical properties when observed as a whole. Acoustic losses are relevant in metamaterials in the millimeter scale. In addition, their geometry is intricate and challenging for numerical implementation. The results are compared with existing measurements.
Juhl, P. M., Cutanda Henríquez, V., Andersen, P. R., Jensen, J. S., & Sánchez-Dehesa, J. (2017). A numerical model of an acoustic metamaterial using the boundary element method including viscous and thermal losses. Journal of Computational Acoustics, 25(4), . https://doi.org/10.1142/S0218396X17500060