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Supersonic flutter characteristics of cylindrical sandwich panels made of a saturated functionally graded porous (FGP) core and two homogeneous face sheets are studied in this paper based on the Biot’s poroelasticity theory. The third-order shear deformation theory (TSDT) is used to model the panel and the piston theory is hired to estimate the aerodynamic pressure create by the supersonic fluid flow. First, the set of the governing equations are solved numerically via generalized differential quadrature method (GDQM) and natural frequencies are calculated for various boundary conditions. Then, convergence of the solution is confirmed and its accuracy is demonstrated by comparing the results with those reported by other authors. Finally, the effects of geometrical parameters of the panel, thickness of the porous core, porosity distribution pattern, porosity parameter (size of pores), compressibility of pore fluid and yaw angle (fluid flow direction) on the flutter boundaries of FGP sandwich panels are investigated.

In this paper, a numerical solution is presented for free vibration analysis of cantilever functionally graded carbon nanotubereinforced trapezoidal plates. The plate is modeled based on the first-order shear deformation theory, effective mechanical properties are estimated according to extended rule of mixture, and the set of governing equations and boundary conditions are derived using Hamilton's principle. Generalized differential quadrature method is employed, and natural frequencies and corresponding mode shapes are derived numerically. Convergence and accuracy of the solution are confirmed, and effect of various parameters on the natural frequencies is investigated including geometrical characteristics, volume fraction and distribution of carbon nanotubes. Because of similarity of the studied model with the wing, tail and fin of aircrafts and missiles, results of this paper can be useful in design and analysis of aeronautic vehicles in the near future. It is worth mentioning that results of this paper may serve as benchmarks for future studies.

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