摘要:

In this study, a neural network is applied to optimization problems of material compositions for a nonhomogeneous hollow circular cylinder with arbitrarily distributed and continuously varied material properties such as those of a functionally graded material. Using the analytical procedure of a laminated hollow circular cylinder model, the analytical temperature solution for the cylinder is derived approximately. Further more, the thermal stress components are formulated under the mechanical condition as being traction-free and making use of the Airy's stress function method. As a numerical example, the hollow circular cylinder composed of zirconium oxide and titanium alloy is considered. In addition, for the optimization problem of minimizing the thermal stress distribution, the numerical calculations are made using a neural network and the optimum material composition is determined taking into account the effect of the temperature dependency of material properties. Furthermore, the results obtained by the neural network and the ordinary nonlinear programming method are compared.

ISSN:0149-5739    

DOI:10.1080/014957399281020

出版商:Informa UK Ltd    

年代:1999

数据来源: Taylor

摘要:

This article addresses the linear dynamic theory of binary mixtures of thermoelastic bodies. In the first part of this article we establish the continuous dependence of solutions upon initial data and body loads. Then we derive a spatial decay estimate of an energetic measure associated to a dynamical process.

ISSN:0149-5739    

DOI:10.1080/014957399281039

出版商:Informa UK Ltd    

年代:1999

数据来源: Taylor

摘要:

In this study, the theoretical analysis of a three-dimensional thermal stress problem is developed for a functionally graded rectangular plate due to a partial heat supply in a transient state. Assuming the functionally graded rectangular plate has nonhomoge neous thermal and mechanical material properties in the thickness direction, the three-dimensional temperature in a transient state and three-dimensional transient thermal stresses in a simple supported plate for functionally graded material are analyzed by introducing the theory of laminated composites as one of theoretical approximation. As an example, numerical calculations are carried out for a functionally graded rectangular plate made of zirconium oxide and titanium alloy. Some numerical results for the temperature change, the displacement, and the stress distributions are shown in figures.

ISSN:0149-5739    

DOI:10.1080/014957399281048

出版商:Informa UK Ltd    

年代:1999

数据来源: Taylor

摘要:

Thermoelasticity of multilayered cylinders subjected to known temperatures at traction free boundaries are considered. Laplace transform and finite difference methods are used to analyze problems. Using the Laplace transform with respect to time, the general solutions of the governing equations are obtained in transform domain. The solution is obtained using the matrix similarity transformation and inverse Laplace transform. We obtained solutions for the temperature and thermal stress distributions in a transient state. Moreover, the computational procedures established in this article can solve the generalized thermoelasticity problem for a multilayered composite cylinder with nonhomogeneous materials.

ISSN:0149-5739    

DOI:10.1080/014957399281057

出版商:Informa UK Ltd    

年代:1999

数据来源: Taylor

摘要:

A new higher order theory of laminated anisotropic shells for the solution of thermal stress problems that takes into account transverse shear stresses is developed. The theory is based on the kinematic hypotheses that were not assumed a priori but derived on the basis of an iterative technique. The hypotheses take into account the influence of the tangential components of the external loads and the temperature on distributions of the transverse shear stresses through the thickness of the shell. Some analytical solutions are obtained on the basis of the theory developed, and the results are compared with those available in the literature. The theory is also implemented on the basis of the finite element method, and a new triangular finite element is formulated. Some numerical results on the basis of this finite element are also presented.

ISSN:0149-5739    

DOI:10.1080/014957399281066

出版商:Informa UK Ltd    

年代:1999

数据来源: Taylor

摘要:

In a joint of two dissimilar materials, stresses at the intersection of the edges and the interface are very high or singular for elastic material behavior. For most joint geometries and material combinations there is a type of r omega singularity. However, for some joint geometries and material combinations there is a type of r omega ln r singularity. In this article, the type of r omega ln r stress singularity will be treated by the Mellin transform method for a joint of two dissimilar materials under thermal loading. The emphasis is placed on the analytical description of the stress distribution near the singular point. The angular functions are given in a general form. They are different from those of the same joint under edge tractions. Two examples are presented to show the good agreement of the stresses calculated by the finite element method and from the analytical description for a finite joint; the unknown factors used to describe the stress distribution are also determined.

ISSN:0149-5739    

DOI:10.1080/014957399281075

出版商:Informa UK Ltd    

年代:1999

数据来源: Taylor

ISSN:0149-5739    

DOI:10.1080/014957399281084

出版商:Informa UK Ltd    

年代:1999

数据来源: Taylor