Effect of distributed axial loading on dynamic stability and buckling analysis of a viscoelastic DWCNT conveying viscous fluid flow

In this article, dynamic stability and buckling analysis of a double-walled carbon nanotube (DWCNT) under distributed axial force are investigated. The visco-Pasternak model is used to simulate the elastic medium between nanotubes considering the effects of spring, shear and damping of the elastic medium. This system is conveying viscous fluid, and the relevant force is calculated by modified Navier-Stokes relation considering slip boundary condition and Knudsen number. The nanostructure is modeled as two orthotropic moderately thick cylindrical shells, and the effects of small-scale and structural damping are accounted based on modified couple stress and Kelvin-Voigt theories. The governing equations and boundary conditions are developed using Hamilton's principle and solved with the aid of Navier and generalized differential quadrature methods. In this research, the dynamic instability occurs in the viscoelastic DWCNT conveying viscous fluid flow as the natural frequency becomes equal to zero. The results show that the velocity of viscous fluid flow, axial load, mode number, length-to-radius ratio, radius-to-thickness ratio, visco-Pasternak foundation and the boundary conditions play important roles on the critical pressure and natural frequency of the viscoelastic DWCNT conveying viscous fluid flow under axial force.