Buckling instability of double-wall carbon nanotubes conveying fluid

It is of fundamental value to understand the vibrations and instability of carbon nanotubes conveying fluid. In this paper, by using a multi-elastic beam model in which the intertube radial displacements and the related internal degrees of freedom are considered, the natural vibrations and buckling instability of double-wall carbon nanotubes (DWNTs) conveying fluid with simply supports at both ends are investigated. It is found that the resonant frequencies depend on the fluid flow velocity, and that buckling instability of the DWNTs occurs at a critical flow velocity. In particular, some new, interesting and sometimes unexpected results are shown and discussed.