Flexural wave band gaps in fluid-loaded periodic plates

In this paper, the flexural wave attenuation characteristics of a periodic plate subjected to fluid loading are investigated. A unified approach developed from the finite element method is proposed for predicting the frequency band gap of the fluid-loaded plate. The proposed approach is able to deal with the cases which exhibit a more general material distribution in the unit cell model. Numerical results are given to show the dispersion relation of the fluid-loaded phononic plate. Furthermore, the band gap diagrams of periodic plates with different material distribution and characteristics are investigated. The comparison results show that the relative change of band gap width induced by fluid loading does not keep a constant trend, the band gap can be broadened or narrowed and is essentially dependent on the coupling effects of material distribution and property characteristics.