Investigation Of effects Of Structural Defects On A Phononic Crystal Heterostructure Waveguide

Phononic crystals are inhomogeneous structures which are created by periodic arrangement of inclusions in an elastically different host material. By removing of a row of inclusions, phononic crystal waveguide can be obtained. In this research, effects of structural defects on a phononic crystal heterostructure waveguide have been investigated. The heterostructure is composed of square and triangular phononic crystals (periodic arrangement of steel inclusions in epoxy host). To analyze the structure, displacement based finite difference time domain method has been used. The simulation shows that a stub attached vertically to the heterostructure waveguide induces dips in the transmission spectrum. Also, the frequency range of the transmission was limited to a narrow frequency domain of 104 Khz in the cavity-containing waveguide. Finally, the simulation showed that the effect of the cavity that is inserted at the side of the waveguide is insignificant.Phononic crystals are inhomogeneous structures which are created by periodic arrangement of inclusions in an elastically different host material