Eur. Phys. J. Plus (2021) 136: 930
https://doi.org/10.1140/epjp/s13360-021-01927-6

Regular Article

Stability analysis of embedded axially functionally graded nanotubes containing flow with spinning motion under an axial load based on generalized differential quadrature method

¹ Jilin Jianzhu University of Changchun, 130118, Changchun, China
² HIT (Hainan) Military-Civilian Integration Innovation Research Institute Co., LTD, 572400, Hainan Province, China
³ Department of Mechanical Engineering, Imperial College London, SW7 2AZ, London, UK

^a chenjiaoge@163.com
^d pooyansafari1@gmail.com

Received: 15 March 2021
Accepted: 11 August 2021
Published online: 12 September 2021

Abstract

In the present study, the dynamics of Y-shaped axially functionally graded nanoscale tubes transmitting flow with spinning motion in hygro-magnetic fields subjected to an axial load are surveyed based on the nonlocal strain gradient theory (NSGT). Scale-dependent dynamic equations are derived by exploiting Hamilton's principle. The generalized differential quadrature method is adopted, and the model equations are numerically solved. Backward and forward whirling frequencies, instability thresholds are obtained. Also, a parametric study is accomplished to explain the influence of key parameters such as axial material gradation, elbow inclination angle, complex environments, scale factor, spin and flow velocities on the system behavior. It is discovered that by considering simultaneous softening effects of axial load and moisture environments, the flutter condition could happen instead of divergence instability. Meanwhile, it is established that when the scale factor is greater than unity, the stabilizing effect of the strain gradient parameter dominates the system stability. Furthermore, the outcomes show that compared with homogeneous structures, it is possible to significantly enhance the stability performance of the axially graded systems by fine-tuning material characteristics.