title: Homogenization of two-dimensional clusters of rigid rods in air.
abstract: The scattering of sound waves by circular-shaped clusters consisting of two-dimensional distributions of rigid cylinders in air is studied in the low-frequency limit (homogenization) both theoretically and experimentally. Analytical formulas for the effective density and sound speed are obtained in the framework of multiple scattering. Here, an experimental demonstration is reported in which a cluster of wooden rods acoustically behaves as a cylinder of argon gas. Moreover, evidence is presented indicating the validity of the homogenization in this cluster at frequencies lower than 3 kHz, which corresponds to a wavelength that is only 4 times the parameter of the embedded lattice and is a quarter of the cluster's diameter.
authors.affiliation: Wave Phenomena Group, Nanophotonics Technology Center, Polytechnic University of Valencia, C/Camino de Vera s/n, E-46022 Valencia, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Torrent
authors.forename: Andreas
authors.initials: A
authors.lastname: Håkansson
authors.forename: Francisco
authors.initials: F
authors.lastname: Cervera
authors.forename: José
authors.initials: J
authors.lastname: Sánchez-Dehesa