両端に波動ブラックホールを有するリブ用構造の減衰解析

抄録

This paper deals with vibration damping analysis using finite element method (FEM) with Strain Energy Method for rib structures having acoustic black holes at both sides at of the plate. This rib model has acoustic black holes at both sides. Damping materials are laminating on the acoustic black holes. And the rib structure is supported by linear spring in the middle of the model. We calculated 1 st~50 th order mode of modal loss factors and eigenmodes of the models by using FEM. And we select 10 modes with similar deformations between two models. The base model is a rib structure with acoustic black holes at both sides and a damping material at the top, and the comparison model is a rib structure without acoustic black holes and with only a damping material. We clarified the effect of the acoustic black hole on the modal damping for each eigenmode. As a result, it became clear that the value of the modal loss factor increased significantly by adding acoustic black hole. In particular, it is found that fixing both sides where the acoustic black holes are located increases the damping of low-order modes.