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Abstract CNT (Carbon nanotube)-based fluidic systems hold a great potential for emerging medical applications and nano-electromechanical systems (NEMS). One of the critical issues in designing such fluid structure interaction (FSI) systems is how to avoid the vibration induced by the fluid flow, which is undesirable and may even promote the dynamic structural instability. The main objective of the present research is to investigate the flutter instability of a cantilevered single-walled carbon nanotube (SWCNT) induced by fluid flow under a longitudinal magnetic field and different temperature fields. To obtain a dynamical model for the system, the CNTs are modeled as nonlocal Euler–Bernoulli beams. The governing partial differential equations of the transverse vibration and associated boundary conditions are derived by Hamilton’s principle. Then, the differential transformation method (DTM) is applied to solve the governing equations of the FSI systems, and some numerical examples are presented to investigate the effects of nonlocal parameters, temperature and longitudinal magnetic field on the critical flow velocity at which flutter may occur. Numerical results show that the nonlocal small-scale parameter makes the fluid-conveying CNT more flexible, and the addition of a temperature field leads to much richer dynamic behaviors of the CNT system. The above analytical results obtained are found to be in good agreement with those presented in the literature. More importantly, it can be concluded that no matter what the temperature field is, the critical flutter velocity will be improved significantly by applying a longitudinal magnetic field, although there exists an upper limit for this enhancement, which is dependent on temperature variation. The numerical results demonstrate that to improve the dynamic stability of the nanoscale FSI systems, it is not reasonable to just increase the intensity of the axial magnetic field. Thus, the results of the present study may facilitate further analysis of nonlocal vibration, and the design of nanotubes in the presence of multi-physics fields.
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Received: 24 January 2020
Published: 22 February 2021
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2021, Vol. 42 
