Calculational and Experimental Investigations into the Effects of the Scatterer and Matrix on Phononic Crystals Properties

Three-dimensional phononic crystals based on the locally resonant structure were fabricated in this work. The effects of the physical properties of the scatterer and matrix on the acoustic absorption coefficient (AAC) were investigated via calculational and experimental methods simultaneously. The consistency of calculational and experimental results was examined. Two kinds of backing of standing wave tube, air and steel-air backing, were used to validate the changing discipline of AAC. The results suggested that the location, extension and intensity of resonant peak had the close relationship with the modulus and thickness of the scatterer's coating layer, and the modulus of matrix. The type of backing also influenced the AAC of phononic crystals.