Finite Element Analysis of Damping Characteristics of Flat Plate with residue thicknesses and half crater new type acoustic black holes

Abstract

This paper deals with vibration damping analysis using finite element method with Model Strain Energy Method for flat plate having new type acoustic black holes. The new acoustic black holes have half craters and residue thicknesses on both sides of the flat plate. Viscoelastic vibration damping materials are laminated over the acoustic black hole. The flat plate is fixed on two edges where the acoustic black hole does not exist. The damping layer is modeled by linear solid finite elements in consideration of complex modules of elasticity. We calculated modal loss factors and eigenmodes of the models. We clarified effects of the new acoustic black hole on the modal damping for each eigenmode. The results show that having a residue thickness provides damping in the low-frequency range. It was also found that having a residue thickness increases the damping effect.