[EN] Viscous and thermal losses of acoustic waves are usually neglected or accounted for as boundary
impedance. It is known, however, that acoustic losses become relevant in devices with some
dimension in the millimeter range or below. On the other hand, the new class of structures called
acoustic metamaterials can be affected by acoustic losses, but in this case the extension of these effects
is less known. Acoustic metamaterials are intricate periodic structures where, at frequencies low
enough ( corresponding to wavelengths much l arger than the structure period), elementary units
interact producing interesting unusual effects.
In this paper advanced modeling tools based on the Boundary Element Method (BEM) and the Finite
Element Method (FEM) are used to study the effect of losses in an acoustic metamaterial scaled to
different sizes. The conclusions are expected to give insight on the practical limitations when using
acoustic metamaterialsJ. Sanchez-Dehesa acknowledges the support by the Spanish Ministerio de Economía y Competitividad, and the European Union Fondo Europeo de Desarrollo Regional (FEDER) through Project No. TEC2014-53088-C3-1-RCutanda Henriquez, V.; Andersen, PR.; Sánchez-Dehesa Moreno-Cid, J. (2016). Numerical modeling of double-negative acoustic metamaterials: Should losses be included?. Universidade do Porto. 1-8. http://hdl.handle.net/10251/181075S1