Torsional vibration and buckling of the cylindrical shell with functionally graded coatings surrounded by an elastic medium

In this study, the torsional vibration and buckling analysis of cylindrical shell with functionally graded (FG) coatings surrounded by an elastic medium is investigated. The material properties of FG coatings are assumed to be graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents. A two-parameter foundation model or Pasternak foundation model is used to describe the shell-foundation interaction. The basic equations are derived and solved by using Galerkin method and the expressions for dimensionless torsional buckling load and dimensionless torsional frequency parameter of the cylindrical shell with FG coatings resting on the Pasternak elastic foundation are obtained. Finally, the influences of geometrical parameters, volume fraction distribution of FG coatings and foundation stiffnesses on the dimensionless torsional buckling load and dimensionless torsional frequency parameter are discussed. The present results are compared with the available data for a special case. (c) 2012 Elsevier Ltd. All rights reserved.