Aeroelastic flutter analysis of tilted curved nanopipe in supersonic flow

Abstract

One of the novel applications of nano-scale structure is in the field of sensors in supersonic flow conditions. In this regard, a cylindrical nano-scale structure made of two-dimensional functionally graded (2D-FG) material in two-phase supersonic flow condition is considered in this study to explore the state of instability and flutter. It is obvious from the problem definition that several aspects from different fields have to be incorporated into the formulation of the problem. First, the small scale of the structure enforced the utilization of size-dependent theories of elasticity. Here, the nonlocal strain gradient theory is utilized to relate the stress and strain fields together. Moreover, the strain field of the cylindrical structure is computed from assumed displacement fields from higher-order shear deformation theory (HSDT). On the other hand, the equations of motion and boundary conditions are obtained using Hamilton’s principle considering the variational of all the work and energy components. The external energy of the system comes from the pressure loading from the aerodynamic supersonic flow. The validation and convergence examination of the presented method is conducted and a detailed parametric study is performed to find the most important parameter affecting the stability of the nanopipe structure. It is revealed that the Mach number and gas volume fraction of two-phase supersonic flow is extremely influential in determining flutter in the nanopipes.