VIBRATION CHARACTERISTICS OF PERIODIC STRUCTURE WITH MICRO OCTAGON-LIKE UNIT CELL

Abstract

Encouraged by the fact that dynamic damping systems possess high damping characteristics, the paper aims at researching the effect of weight of the sphere embedded into the unit cell of periodic structures on the vibration characteristics of the structure. Firstly, two periodic structure models with micro octagon-like unit cell are built: one is with a heavy sphere in the unit cell, another is without the sphere. In the unit cell of the two models, all the edges are made of aluminum and all the other areas are filled with rubber. Secondly, the preconditioned conjugate gradient method is applied to solve the vibration problem, thus the displacement transfer function-frequency curves of nodes in models are obtained. Finally, several numerical examples with or without sphere in the unit cell are presented. Simulation results show the periodic structure model with a sphere in the unit cell has the advantage of vibration alleviation; in addition, when the weight of the sphere in the unit cell is chosen properly, the band-gap starting frequency and cut-off frequency can drop sharply, the band gap range can become wider, and effect of vibration alleviation can be improved much better within a given frequency range.

DOI: http://dx.doi.org/10.5755/j01.mech.18.1.1285