Macroscopic sonic crystals in a wave guide

Periodical arrays of long, parallel cylinders have been shown in the published literature to exhibit acoustical properties which are analogous to the electronic properties of certain crystalline solids. Thus there are frequency bands for which no acoustic propagation through the array is allowed, with those band gaps being directionally dependent. The properties of such arrays in wave guides are examined in this work. Particular emphasis is put in investigating the properties of those arrays in wave guides that are idealized models of shallow water oceanic wave guides. The effects of those arrays on the propagation of normal modes is investigated in detail. The possibility of using such arrays in the construction of large scale underwater devices such as filters and lenses is also discussed.