Parametric excitation analysis of a piezoelectric-nanotube conveying fluid under multi-physics field

In this study, nonlinear vibration of a carbon nanotube conveying fluid is investigated. The nanotube is covered by a piezoelectric layer and is subjected to a magnetic field. It is assumed that the structure is rested on Winkler---Pasternak foundation and, the Euler---Bernoulli beam theory is employed to establish the governing equations of motion for the vibration behavior of the system. The slip boundary condition of CNT conveying fluid is considered based on Knudsen number and the mathematical modeling of the structure is developed by means of Hamilton's principle. Then, the Galerkin method is employed to discretize the equations of motion and the frequency response of the system is extracted by applying the multiple scale method for piezoelectric-based parametric excitation. It is shown that nonlocal-affected terms and Knudson number have major unpredictable effects on natural frequency, critical fluid velocity and frequency response of the system and one should precisely consider their effects. Also it is shown that approaching to the resonance frequency of the system from lower or greater values highly affects the response of the system which is recommended to be considered.