Thermal post-buckling and snap-through instabilities of FGM panels in hypersonic flows

摘要

The thermo-mechanical behaviors of functionally graded material (FGM) panels are investigated in hypersonic airflows. Present study deals with the three types of material such as power-law FGM (P-FGM), sigmoid FGM (S-FGM) and exponential FGM (E-FGM) models. Based on the first-order shear deformation theory of plate and von Karman strain-displacement relations are adopted in the formulation. Also, the non-linearity is considered as a model for the aerodynamic loads, and thus the pressure is evaluated using the third-order piston theory. Newton-Raphson iterative method is applied to solve the thermal post-buckling behavior in the numerical analysis. In order to validate the modeling and formulation, present results are compared with the previous data. More works reveal that the thermal or aerodynamic loads exceed a critical value, then the panel snaps to the opposite equilibrium position in this study. Especially, snap-through instabilities are more deeply investigated in the thermal post-buckling behavior of FGM panels in hypersonic regimes.