Flow-induced dynamics of carbon nanotubes.

The high aspect ratio and bending resilience of a carbon nanotube (CNT) enables it to have remarkable responses to fluid flow. The structural deformation and vibration of a CNT under fluid flow are discussed in this paper, closely tied to their applications in mechanosensing and energy harvesting. We perform molecular dynamics (MD) simulations and a theoretical analysis based on the elastic beam theory, and find that the performance of these applications is critically defined by thermal noise at low flow speeds and flow-induced elastic instabilities at high speeds. We provide a map of operating mechanisms as defined by the properties of both nanostructures and fluid. The results and understanding obtained here could shed some light on the design of nanomechanical devices operating in fluidic environments.