Flexural Waves Bandgap Analysis and Control in Pipeline Metamaterial Systems

To effectively control the vibration of the pipeline systems, this paper designs a periodic local resonance pipeline metamaterial and investigates the propagation characteristics of flexural waves. The dispersion relationship is derived by using the transfer matrix method (TMM) combined with Bloch’s theorem, and the bandgap results are verified through finite element simulation. The results indicate that there are three bandgaps and three passbands within the frequency range of 0–400[Formula: see text]Hz, with the first passband having a very narrow frequency range and the second and third passbands having a wider frequency range. In order to interpret the influence of pipeline parameters on vibration transmission characteristics, the control variable method is used to analyze parameters such as unit cell length, pipe thickness, and inner diameter size. Subsequently, single-degree-of-freedom and multi-degree-of-freedom resonators are introduced to effectively control specific passbands. The position of the resonator in the pipeline is changed, and the optimal installation position of the resonator is determined through finite element analysis. Further, the bandgap characteristics of pipelines under two different support conditions are investigated and discussed. This study provides theoretical support for vibration control of pipeline structures and could be applied to the design of low-frequency vibration reduction.