Novel vibration self-suppression of periodic pipes conveying fluid based on acoustic black hole effect

The pipes conveying fluid are concerned as extremely significant fluid-solid coupling structures due to the extensive application in the many engineering fields, but poor operating performances induced by unexpected vibration may destroy the related devices in the piping structures. To effectively attenuate the fluid-solid coupling vibration, a novel control technique is proposed to realize the vibration self-suppression of pipes conveying fluid with integration of the periodic acoustic black hole (ABH) wedges inspired by the extraordinary band gaps (BGs) behaviors of the metamaterials. On the basis of the Euler-Bernoulli (E-B) beam model, the mechanical model and dynamic equations are established by using Hamilton's principle. By applying the spectral element method (SEM) in conjunction with the transfer matrix method (TMM), as well as considering the Bloch theorem, the mechanism of elastic-wave distributions of such periodic ABH pipes conveying fluid are disclosed through investigating the BGs characteristic, frequency response and wave shapes. The results show the proposed technique can effectively form BGs in low frequency bands, and most of the energies are absorbed and scattered by the wedge edge of the pipes in the wave propagation. More importantly, by adjusting the system parameters, the proposed structure can enlarge the BGs regions and transfer it to the low frequency bands. It provides a simple design scheme for the manufacture of pipe conveying fluid with ultra-wide BGs.