Development of thermoelasticity equations for strains
Abstract
It is well known that thermal stresses play an important role in various technological problems and are often determined by solving the boundary value problem of thermoelasticity with respect to stress and temperature. Typically, solving such problems reduces to solving the biharmonic equation for the Airy stress function. This article is devoted to the formulation of thermoelasticity problems with respect to strain and temperature and their numerical solution. In the framework of the strain compatibility conditions two versions of thermoelasticity boundary value problems in strains and temperature are formulated. The first thermoelasticity problem consists of three off-diagonal differential equations obtained from the strain compatibility conditions and three equilibrium equations expressed in terms of the deformations. In the second case, the boundary value problem of thermoelasticity is reduced to a system of six Poisson differential equations for the components of the strain tensor and temperature. The discrete analogs of the boundary value problems are constructed using the finite difference method. The plane problem of a rectangular plate located in a temperature field has been solved numerically. Comparison of numerical results with known ones shows the validity of the proposed thermoelasticity boundary value problems in strains and the reliability of the obtained results. The proposed equations of the model allow for a more accurate study of the stress-strain state of solids, taking into account temperature, and a more accurate determination of the limits of the safety margin and reliability of structures