ENERGY HARVESTING OF EXTERNAL DOUBLE PIEZOELECTRIC ACOUSTIC BLACK HOLE BEAM

Since acoustic black hole (ABH) can accumulate the vibration energy, the purpose of vibration control and energy harvesting can be achieved by attaching the viscoelastic layer or the piezoelectric layer. In recent years, the dynamic behaviour of embedded piezoelectric acoustic black hole (EABH) has been investigated. The advantage of EABH has been fully demonstrated. However, the reduction of the acoustic black hole thickness will inevitably lead to the weakening of structural strength, the application of ABH in actual engineering is limited. In this paper, an integrated acoustic black hole beam with double piezoelectric layer is proposed and connected to the primary structure. A semi-analytical Gaussian expansion (GE) theoretical model is developed to describe the dynamic behaviour of the coupling structure based on the framework of the Rayleigh-Ritz method. The accuracy of the semi-analytical theoretical model is verified by a reference finite element (FE) model. In order to increase energy harvesting in integrated ABH, a new design for the distribution of piezoelectric patches is developed in order to avoid the location of strain nodes and reach maximum energy harvesting for integrated ABH. The results show that the new design can improve the energy harvesting for integrated ABH through the distribution of piezoelectric patches over a broadband frequency.