Papers by Keyword: Thermoelasticity

Abstract: In the formulation of thermoelasticity and in the framework of the conventional theory of thermal stresses, the problem on the stress state of an elastic piecewise-homogeneous plane or an infinite plate at non-uniform steady-state heating is considered. On the interface of dissimilar materials, the compound plane is reinforced by a collinear system of absolutely rigid thin inclusions and is subjected to mechanical and thermal influences. First, to determine the temperature distribution in a piecewise-homogeneous plane the corresponding boundary value problem of the theory of steady-state heat conduction is solved using the integral Fourier transform. Solving this problem is reduced to solving a singular integral equation (SIE) that allows an exact solution. Further, the elastic displacements of points of the compound plane, caused by mechanical and temperature influence, are determined by the known methods of thermoselasticity. Based on these results, solving the problem of the contact interaction between the system of inclusions and a compound plane is again reduced to solving SIE, which also allows an exact solution. A special case is considered.

Abstract: In this paper, we consider the problem of determining the basic characteristics of the stress state of a composite in the form of a piecewise homogeneous elastic layer reinforced along its extreme edges by stringers of finite lengths and containing a collinear system of an arbitrary number of cracks at the junction line of heterogeneous materials. It is assumed that stringers along their longitudinal edges are loaded with tangential forces, and along their vertical edges - with horizontal concentrated forces. In addition, the cracks are laden with distributed tangential forces of different intensities. The case is also considered when the lower edge of the composite layer is free from the stringer and rigidly clamped. It is believed that under the action of these loads, the composite layer in the direction of one of the coordinate axes is in conditions of anti-flat deformation (longitudinal shift). Using the Fourier integral transform, the solution of the problem is reduced to solving a system of singular integral equations (SIE) of three equations. The solution of this system is obtained by a well-known numerical-analytical method for solving the SIE using Gauss quadrature formulas by the use of the Chebyshev nodes. As a result, the solution of the original system of SIE is reduced to the solution of the system of systems of linear algebraic equations (SLAE). Various special cases are considered, when the defining SIE and the SLAE of the task are greatly simplified, which will make it possible to carry out a detailed numerical analysis and identify patterns of change in the characteristics of the tasks.

Abstract: Considerable thermal stresses arising in thin-walled metallic materials and structures loaded with tensile stresses can lead either to their complete destruction or to the appearance of discontinuity zones in them.

Abstract: The effect of a moving arc spot on a material of a plasmatron electrode is considered in the present paper. Temperature-dependence of material thermophysical properties is taken into account. Dynamics of temperature and thermal stresses fields are calculated. The characteristic feature of temperatures distribution along radius of an electrode is large gradient of temperatures in a narrow zone near to a surface which can cause large thermostresses and microcracks.

Abstract: Solutions within the framework of linear uncoupled thermoelasticity, are presented here for simply supported infinitely long anisotropic cylindrical shell panels subjected to thermal gradient. Benchmark numerical results in the form of displacements and stresses are tabulated for certain angle-ply layup useful for the assessment of improved shell theories.

Abstract: This paper presents an analytical approach for solution of the plane-strain problem on elastic equilibrium of a layer whose material properties are arbitrary functions of the transversal coordinate. The layer is stressed by distributed temperature field under given displacement of its limiting surfaces. By making use of the explicit solution of the relevant problem in terms of stresses, the boundary tractions are determined by the given boundary displacements and temperature field on the basis of established one-to-one relations. In such manner, the original problem is reduced to the problem with boundary conditions in terms of stresses.

Abstract: Geometrically nonlinear model and numerical solutions of large deformation of imperfect functionally graded materials conical shell subjected to both mechanical load and transversely non-uniform temperature rise are given. The material properties of functionally graded shell 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. On the basis of geometrically nonlinear theory of shell, governing equations of the axi-symmetrical deformation are derived. Numerical solutions are obtained by using a shooting method.

Abstract: In this paper, we give a second-order two-scale (SOTS) computational method for composite plate with 3-D periodic configuration under condition of coupled thermoelasticity by means of construction way. Based on the Reissner-Mindlin deformation pattern and integral projection operator of temperature, the homogenization solution is obtained. The SOTS's approximate solution is constructed by the cell functions and the homogenization solution. A set of numerical results are demonstrated for predicting the effective parameters, the displacement and temperature of composite plate. It shows that SOTS's method can capture the 3-D local behaviors caused by 3-D micro-structures well.

Abstract: The higher order two-scale finite element errors of the thermoelastic problem in perforated composites with boundary layer are presented, and the two-scale finite element method coupled with boundary layer is built for analyzing the coupling problem. The numerical results show that the basic configuration and the local temperature strongly affect local strains and local stresses.

Abstract: In this paper, a new solution is presented for one-dimensional steady-state mechanical and thermal stresses in a FG rotating hollow disk and cylinder. The material properties for FG are expressed as nonlinear exponential functions through the radius and Poisson’s ratio is taken to be constant. The temperature distribution is derived from first law of thermodynamics by solving energy equation, with a general thermal and mechanical boundary conditions on the inside and outside surfaces. Heat conduction and Navier equations are solved analytically by choosing elliptic cylinder coordinates system and the results are shown for displacement and stress components along the radial direction.