A new approach of vibration isolation analysis of periodic composite structure based on phononic crystal

It is well-known that phononic crystal has a good effect of vibration isolation within some frequency range. The transmission performances of elastic waves propagating in three-dimension composite structure, based on phononic crystal, embedded periodically with spherical scatterers with different mass density and Lame coefficients are analyzed by the transfer matrix method in this paper. The transfer matrix of monolayer structure and the entire structure are deduced by the wave equations considering boundary conditions of displacement and stress continuity between layers, the reflectivity and transmissivity of vibration isolation of the structure are obtained by calculating its effective impedance, and some useful conclusions are drawn after numerical simulation is carried out.