Vibration reduction of car body based on 2D dual-base locally resonant phononic crystal

Due to the coating feature and bandgap adjustability of dual-base locally resonant phononic crystal (LRPC), the purpose behind this paper is to explore the application of dual-base LRPC in vibration reduction of car body. In previous research, the band structure and its influencing factors of dual-base LRPC have been investigated theoretically. As an artificial periodic structure, the key factors of application, including the number of unit cells, the curvature of base panel and the boundary constraint, have been taken account into analyzing bandgap characteristics of dual-base LRPC by finite element method (FEM). The results indicate that the non-infinite dual-base LRPC structure with small curvature and boundary constraint can still produce the expected bandgap. Then, according to the acoustic contribution analysis, the floor has been determined as the target panel for vibration reduction, on which the dual-base LRPC has been conducted. In order to obtain the wider bandgap with less added mass, the lattice constant and stiffness have been matched and optimized. With the final arrangement, the total body vibration level sharply reduces by 15 dB, and the interior noise reduces by 9 dB as well. It provides a new method for the vibration reduction of car body. (C) 2019 Elsevier Ltd. All rights reserved.