One of the common failure modes of thin cylindrical shell subjected external pressure is buckling. The buckling pressure of these shell structures are dominantly affected by the geometrical imperfections present in the cylindrical shell which are very difficult to alleviate during manufacturing process. In this work, only three types of geometrical imperfection patterns are considered namely (a...

In this article, a nonlinear dynamical investigation of porose functionally graded cylindrical panels using proposed analytical model is carried out. The material's properties are considered to be porosity-dependent and in the thickness direction, corresponding power-law distribution. classical shell theory, with geometrical shape von Karman–Donnell, employed get Lagrange motion equations. By a...

Functionally graded materials (FGM) in the form of layered structure consisting of yttria stabilized zirconia (8 mol% Y2O3) and nickel were fabricated by spark plasma sintering procedure. The relative density, linear shrinkage and Vickers hardness of each layer of graded materials were measured. The microstructure and the composition of these components were studied. The results obtained show t...

In this paper the vibration of a spinning cylindrical shell made of functional graded material is investigated. After a brief introduction of FG materials, by employing higher order theory for shell deformation, constitutive relationships are derived. Next, governing differential equation of spinning cylindrical shell is obtained through utilizing energy method and Hamilton’s principle. Making ...

Linear eigenvalue analysis of cracked cylindrical shells under combined internal pressure and axial compression is carried out to study the effect of crack type, size and orientation on the buckling behavior of cylindrical thin shells. Two types of crack are considered; through crack and thumbnail crack. Our calculations indicate that depending on the crack type, length, orientation and the int...

In this paper the idea of a Layered CAD is introduced, a truncation of a CAD to only high dimensional cells. Limiting to full-dimensional cells has already been investigated in the literature, but including another level can be beneficial for applications. A related topological property is defined and related to robotics motion planning. The distribution of cell dimensions in a CAD is investiga...

FGM components are generally constructed to sustain elevated temperatures and severe temperature gradients. Low thermal conductivity, low coefficient of thermal expansion and core ductility have enabled the FGM material to withstand higher temperature gradients for a given heat flux. Examples of structures undergo extremely high temperature gradients are plasma facing materials, propulsion syst...

1. Abstract Functionally Graded Materials (FGMs) possess continuously graded material properties and are characterized by spatially varying microstructures. Such materials are studied in conjunction with the concept of topology optimization design which determines holes and connectivities of the structure by adding and removing material in the extended fixed design domain. The objective is to d...

Structural optimization using computational tools has become a major research field in recent years. The paper deals with a sizing optimization analysis of laminated circular cylindrical shell. For thin-walled shells, the classical shell theory is capable of accurately predicting the shell behavior. The weight minimization subjected to displacement constraint within the numerical optimization o...

in this study, thermo-mechanical nonlinear vibration of a polyethylene (pe) cylindrical shell embedded in an elastic foundation was investigated. the shell is reinforced by armchair carbon nanotubes (cnts) where characteristics of the equivalent composite being determined using mori-tanaka model. the elastic medium is simulated using the spring constant of the winkler-type,  . employing nonline...