Effect of flow pulsations on chaos in nanotubes using nonlocal strain gradient theory

In this article, a chaos analysis is performed for the nonlinear coupled dynamics of nanotubes conveying pulsatile fluid for the first time. A size-dependent advanced elasticity model is developed with consideration of stress nonlocality as well as the gradient of strain components. After deriving the nonlinear motion equations using Hamilton's approach, they are numerically solved via application of a time-integration technique for a system with a high-dimensional degree of freedom. Chaos analysis is performed for the nanotube at both subcritical and supercritical flow regimes. Both mean fluid velocity and the amplitude of velocity pulsation are varied as the bifurcation parameter. The proposed size-dependent continuum modelling and numerical results would be useful in order to tailor the system parameters to avoid chaos in nanoelectromechanical devices using fluid-conveying nanotubes.