vibration analysis of different types of porous fg conical sandwich shells in various thermal surroundings

Vibration behavior of different types of porous functionally graded (fg) conical sandwich shells are investigated based on a modified high order sandwich shells theory for the first time. sandwich shell includes fg face sheets covering a homogeneous core and the second one includes homogeneous face sheets and a fg core. power law rule modified by considering two types of porosity distributions is used to model the functionally graded materials. all materials are temperature dependent and uniform, linear and nonlinear temperature distributions are used to model the effect of the temperature variation in the sandwiches. governing equations are obtained by the hamilton’s energy principle and solved with galerkin method. to verify the results, they are compared with ones achieved by finite element method obtained by abaqus software for special cases with the results in literatures.