Fluid-structure interaction and band gap analysis of periodic composite liquid-filled pipe

This paper studies the vibration band gap characteristics of a liquid-filled composite pipeline. The transfer matrix method is used to create a one-dimensional fluid-structure interaction model of the composite pipeline from the constitutive equation, physical equations, and boundary conditions of the anisotropic material. A phononic crystal pipeline is designed with a periodic arrangement on the axial pipe wall. The method used to analyze the fluid-structure interaction of liquid-filled composite and phononic crystal pipelines is verified by comparing responses with finite-element method results. The results' agreement demonstrates the method's and calculation code's correctness. Furthermore, the band gaps for an empty composite phononic crystal pipe, water hammer, and a liquid-filled pipe are calculated by Bloch vector theory, and the effects of fluid-structure interaction and the composite parameters on the three band gap characteristics are analyzed. The numerical results show that Poisson's coupling affects the band gap at some frequency points, while the laying angle and fiber volume fraction in the composite pipe influence the band gap length and amplitude change. The research results of this paper provide a reference for the design and vibration control of liquid-filled composite pipelines.