Dynamic stability of cylindrical nanoshells under combined static and periodic axial loads

The dynamic stability of cylindrical nanoshells subjected to combined static and time-dependent periodic axial forces is studied by employing the two-dimensional nonlocal elasticity theory together with the first-order shear deformation theory of shells. The differential quadrature method as an efficient and accurate numerical technique is applied to discretize the equations of motion under different boundary conditions in the spatial domain and transform them into a system of coupled Mathieu-Hill-type equations in time domain. Subsequently, the Bolotin's first approximation method is employed to extract the dynamic instability regions of the cylindrical nanoshells. The approach is validated by showing its fast convergence rate and carrying out comparison studies with existing results in the limit cases. Afterward, the effects of the nonlocal parameter, length and thickness-to-mean radius ratios together with different boundary conditions on the principal dynamic instability regions of the cylindrical nanoshells are studied in detail.