Thermal buckling analysis of bi-directional FGM doubly curved shell panels using a TSDT p-version finite element method

Unlike previous studies that predominantly focused on uni-directional functionally graded materials (FGMs), this work extends the analysis to bi-directional FGM shell panels with various geometries, offering a more comprehensive understanding of their thermal buckling behavior. For the first time, a combination of higher-order shear deformation theory and the p-version finite element method is utilized in this context. Moreover, a novel nonlinear temperature distribution solution derived from the steady-state thermal conduction equation for bi-FGMs is proposed, addressing a significant gap in the existing literature. The investigation explores the effects of curvature, aspect ratio, thickness ratio, and material gradient on the buckling response of shell panels under thermal loading. The study begins with the mathematical formulation of the problem, laying the groundwork for the subsequent analyses. To ensure the accuracy and effectiveness of the custom-made code, a rigorous comparative study is performed. The analysis then extends to examining the impact of material gradient indexes on the shell’s behavior, focusing on variations in buckling temperature rise, mode shapes, and normalized modal stress distribution. Additionally, the investigation includes a comparative analysis of three different types of temperature distributions, considering both temperature-dependent and temperature-independent material scenarios.