A New Model for the Two-Dimensional Acoustic Cloak

A new formula is proposed for a two-dimension anisotropic acoustic cloak based on the sound speed matching and sound boundary impendence matching. In this model, a crucial parameter is involved in the expression for the acoustic cloak material. Based on the effective medium approximation theory, the acoustic cloak is reconstructed with multilayered structure composed of homogeneous isotropic materials. The proposal formula exhibits different exponent variables to investigate the invisible effects of the acoustic cloak The real part distributions of the pressure field demonstrate that the incident wave could pass through the acoustic cloak with an unchanged wavefront direction during an appropriate region for the exponent variable. The proposed design of the acoustic cloak could be applied as guidance for the multilayered acoustic cloak composed by existing material in reality.