Porous Functionally Graded Cylindrical Shells’ Buckling Study

Abstract

Traditionally, shell finite elements are best suited for the numerical simulation of thin structure applications, while solid elements are regularly used for bulk structures. However, engineering structures often combine thin components with thick/bulk geometries in the same assembly. Thus, the finite element modeling of such applications would be considerably simplified if the same type of finite element could be successfully used in both zones. Further, functionally graded material (FGM) have been broadly applied to numerous engineering applications such as aerospace, defense, automotive, nuclear power, bio-engineering and other areas. However, the occurrences of porosities are inevitable during the process of manufacturing FGMs. Knowing the mechanical behavior of composite FGM structures taking into account porosities is essential in the design and optimization process of engineering projects. In this paper, a geometrically nonlinear analysis of porous FGM cylindrical shell is investigated. A user defined subroutine (UMAT) is developed and implemented in Abaqus/Standard to study the FG shells in large displacements and rotations. The effects of functionally graded power index, porosity coefficient, porosity arrangements and geometrical design parameters are examined.