MECHANICAL ENGINEERING FILTER BASED ON PHONONIC BAND GAP

In this paper, we introduce a multifunctional structure design combining mechanical wave filtering properties and energy harvesting. The proposed concept is based on the ability of periodic structures to forbid elastic waves from propagation, through specific frequency ranges known as phononic band gaps. We treated the propagation of elastic waves incident normally on 1D phononic crystal. Based on transfer matrix method, we have studied the elastic waves propagation through 1D periodic phononic crystal and quasi-periodic (Fibonacci sequence) phononic crystal. Also we have studied the effect of defect layer from different materials inside the structure, the effect of number and thickness of defect layer on the phononic band gaps and localized waves are discussed as well. These results can be useful in many applications such as mechanical filters and vibration isolation devices.