Thermal nonlinear stability of functionally graded porous material nearly cylindrical shells with surrounding elastic media and tangentially restrained edges

This paper aims to investigate the influences of surrounding elastic media and tangential edge constraints on the buckling and postbucking behaviors of nearly cylindrical shell (NCS) made of functionally graded porous material (FGPM) and subjected to uniform temperature rise. Three different types of porosity distributions are considered and assumed to be in forms of cosine functions of thickness variable. The volume fractions of material constituents are assumed to vary through the shell thickness according to power-law functions. Temperature-dependent material properties and elasticity of tangential constraints of boundary edges are included. Governing equations are established within the framework of classical shell theory taking into account von Karman-Donnell nonlinearity and interactive pressure from surrounding elastic media. Multiterm analytical solutions for simply supported NCSs are assumed and Galerkin procedure is utilized to derive expressions of buckling load and nonlinear load-deflection relation. An iteration process is adopted to determine critical thermal loads and postbuckling temperature-deflection paths. Numerous parametric studies are carried out to assess many different effects on thermal buckling resistance and postbuckling load carrying capabilities. The study reveals that porosity and tangential edge constraint have beneficial and deteriorative influences on the thermal stability of the NCSs, respectively. Furthermore, the obtained results demonstrate that surrounding elastic media have significantly beneficial influences on the thermal nonlinear stability of FGPM NCSs.