In this paper, a study on the vibration of thin cylindrical shells made of a functionally gradient material (FGM) composed of stainless steel and nickel is presented. The effects of the FGM configuration are taken into account by studying the frequencies of two FG cylindrical shells. Type I FG cylindrical shell has nickel on its inner surface and stainless steel on its outer surface and Type II FG cylindrical shell has stainless steel on its inner surface and nickel on its outer surface. The study is carried out based on third order shear deformation shell theory (TSDT). The objective is to study the natural frequencies, the influence of constituent volume fractions and the effects of configurations of the constituent materials on the frequencies. The properties are graded in the thickness direction according to the volume fraction power-law distribution. The analysis is carried out with strains-displacement relations from Love's shell theory. The governing equations are obtained using energy functional with the Rayleigh-Ritz method. Results are presented on the frequency characteristics and the influences of constituent various volume fractions for Type I and II FG cylindrical shells and simply supported boundary conditions on the frequencies. تفاصيل المقالة

This paper presents the study on influence external pressures on vibration of functionally graded materials thin-walled cylindrical shell supported. The functionally graded materials (FGMs) properties are graded in the thickness direction of the shell. FGMs are advanced composite materials, consisting of different types of materials, in which the properties shift continuously from one material on the one side to another material on the other side with a specific gradient. The FGM cylindrical shell supported equations with external pressure are established based on classical shell theory with beam functions as axial modal function. The governing equations of motion were employed, using energy functional and by applying the Ritz method. The boundary conditions represented by end conditions of the FGM structure which are sliding-sliding, clamped-free and clamped-simply supported being considered. This problem was solved with computer programming using MAPLE package. Comparison results are carried out to verify the validity with published papers. The influence of the external pressures, loop support and effect of the different boundary conditions on natural frequencies of FGM thin-walled cylindrical shell are studied. تفاصيل المقالة

In this paper, the influence of the constituent volume fractions by changing the values of the power-law exponent with uniform pressure on the vibration frequencies of reinforced functionally graded cylindrical shells is studied. The FGM shell with ring is developed in accordance to the volume fraction law from two constituents namely stainless steel and nickel. These constituents are graded through the thickness direction, from one surface of the shell to the other and are controlled by power-law volume fraction distribution. The reinforced FGM shell equations with ring and uniform pressure are established based on first order shear deformation theory. The governing equations of motion were employed, using energy functional and by applying Ritz method. The boundary conditions represented by end conditions of the FGM cylindrical shell are simply supported-simply supported, clamped-clamped and free-free. Effects of the different values of the power-law exponent, uniform pressure, reinforced ring and different symmetric boundary conditions on natural frequencies characteristics are studied. To check the validity of the present study, the results obtained are compared with those available in the literature. تفاصيل المقالة

In this paper, influence power-law distribution with pressure on frequencies of the supported functionally graded cylindrical shell is studied. This shell is constructed from a functionally graded material (FGM) with two constituent materials. FGMs are graded through the thickness direction, from one surface of the shell to the next. The supported FGM shell equations are created based on FSDT. The governing equations of the movement were utilized by the Ritz method. The boundary conditions are clamp-sliding and free-simply support. The influence of the various values of the power-law distribution with pressure supported and different conditions on the frequencies characteristics are studied. This study shows that the frequencies decreased with the increase in the amounts of the power-law distribution with pressure. Thus, the constituent power-law distribution with pressure effects on the frequencies. The results show the frequencies with different power-law distribution under pressures are various for different conditions. تفاصيل المقالة