Transformation Acoustics

In this chapter we review the development of the concept of transformation acousticsAcoustics, through which soundSound fields can be arbitrarily manipulated by complex acousticAcoustics materials. We describe the theory and the design equations in several different forms, and we present several explicit design examples using transformation acousticsAcoustics. After briefly describing some theoretical offshoots from the original idea, we conclude with a summary of approaches for engineering compositeComposite materials with the smoothly inhomogeneous and anisotropicAnisotropic properties needed for many transformation acousticsAcoustics devices.