The free vibration and supersonic flutter analyses of a three-directional functionally graded conical panel in a thermal environment

In the present study, free vibration and aeroelastic stability (flutter) analyses are investigated for a three-directional functionally graded material (FGM) conical panel subjected to a yawed supersonic fluid flow in a thermal environment. It is assumed that the material is fabricated from a non- homogeneous combination of metal and ceramic. To describe the material gradation, it is assumed that the volume fractions of the metal and ceramic vary simultaneously in the meridional, circumferential, and transverse directions based on several distribution patterns. The panel is modeled based on the first-order shear deformation theory (FSDT), and the aerodynamic pressure is estimated according to the piston theory. The governing equations are formulated by using Hamilton’s principle and are solved for several boundary conditions by using the differential quadrature method (DQM). The effects of the mass fraction, material gradation, temperature, and boundary conditions on the natural frequencies and critical aerodynamic pressure (CAP) are examined through a parametric study. It is concluded that the flutter boundaries are affected more significantly by the material gradation in the transverse direction than by the material gradation in the meridional and circumferential directions. The present study is the first theoretical work regarding the free vibrational and aerothermoelastic stability characteristics of a three-directional FGM conical panel subjected to a yawed supersonic fluid flow.