Size-dependent vibration of multi-span micropipes conveying fluid based on modified couple stress theory

Abstract

In this article, the size-dependent free vibration and stability of multi-span micropipes conveying fluid are studied. To take the size effect into account, the modified couple stress theory is used to derive the governing equation. And the dynamic stiffness method (DSM) is adopted to determine the natural frequencies. Subsequently, some examples are presented to investigate the effects of fluid velocity and material length scale parameter on stability of the multi-span micropipes conveying fluid. It's found that the natural frequencies and the critical velocities obtained by the modified couple stress theory are higher than those predicted by the classical theory.