An investigation on thermoelastic behaviour of functionally graded thick spherical vessels under combined thermal and mechanical loads

• Autorzy: Alavi F. , Karimi D. , Bagri A.
• Języki publikacji: PL

Abstrakty

EN

Purpose: The subject of this paper is to study the thermoelastic behavior of thick functionally graded hollow sphere under thermal and mechanical loads. The mechanical and thermal properties of FG sphere are assumed to be functions of radial position. Design/methodology/approach: In present study, two methods are used to estimate the effective mechanical properties of FG sphere. One of the simplest methods in estimation of the effective mechanical and thermal properties of a mixture of two constituent materials is the Rule of Mixture (R-M) scheme. Another scheme for estimating the mechanical properties is due to the work of Mori-Tanaka. When the mechanical properties of FG sphere are estimated by using the Mori-Tanaka scheme, thermal material properties of FG body may be determined utilizing the R-M or the other methods which will be discussed as follows. Findings: Results for the temperature, radial displacement, radial stress and hoop stress fields through the geometry of the sphere are give. The figures reveal that some minor difference may be obtained for two schemes and the difference between the results for displacement distribution is larger than difference of temperature and stress distributions. Practical implications: The thermal material properties are obtained utilizing the Hatta-Taya and Rosen- Hashin relations. Also, the mechanical properties are estimated using the Mori-Tanaka scheme. In addition to the methods of approximation of material properties cited above, the rule of mixture scheme for determination of thermal and mechanical properties is also considered and results of these two schemes are compared for two cases of material composition through the geometry of FG sphere. The FG sphere is assumed to be symmetrically loaded and one-dimensional steady-state analysis of isotropic linear thermoelastic FG sphere under combined thermal and mechanical loads is investigated. Solution of the heat conduction equation and the Navier equation are obtained by using the Galerkin finite element method and by generating 100 elements along the radial direction of FG sphere. Originality/value: This paper presents the FEM analysis of a functionally graded thick hollow sphere which its thermal and mechanical material properties only depend on the radial position.

Słowa kluczowe

EN

functionally graded material; hollow sphere; thermal stress

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2008
• Tom: Vol. 31, nr 2
• Strony: 422--428
• Opis fizyczny: Bibliogr. 14 poz., wykr.

Twórcy

autor

Alavi F.

autor

Karimi D.

autor

Bagri A.

• Researchers of Young Researchers Club, Tehran, Iran,

Bibliografia

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