Flow-induced instability of double-walled carbon nanotubes based on an elastic shell model

Abstract

Double-walled carbon nanotubes (DWCNTs) are modeled based on Donnell’s shell theory, and flow-induced instability that is induced when pressure-driven fluid goes through the inner tube at a steady flow velocity is studied. The van der Waals (vdW) interaction between the inner and outer walls is taken into account in the modeling. The numerical simulations show that the vdW interaction has significant effects on the flow-induced instability of DWCNTs. The critical flow velocities and loss of stability are closely related to the ratio of the length to the outer radius. Donnell’s shell model for carbon nanotubes (CNTs) is preferred in simulations because it takes into account the shear effects in the walls. A comparison between the CNTs that are based on a Eulerian beam model and those that are based on Donnell’s shell model shows that when the 50-nm-radius tube length is shorter than 10 μm, the comparative errors between the Eulerian beam and Donnell’s shell models are greatly increased.