A finite element model for a coupled thermo-mechanical system: nonlinear strain-limiting thermoelastic body

Abstract: We investigate a specific finite element model to study the thermoelastic behavior of an elastic body within the context of nonlinear strain-limiting constitutive relation. As a special subclass of implicit relations, the thermoelastic response of our interest is such that stresses can be arbitrarily large, but strains remain small, especially in the neighborhood of crack-tips. Thus, the proposed model can be inherently consistent with the assumption of the small strain theory. In the present communication, we consider a two-dimensional coupled system-linear and quasilinear partial differential equations for temperature and displacements, respectively. Two distinct temperature distributions of the Dirichlet type are considered for boundary condition, and a standard finite element method of continuous Galerkin is employed to obtain the numerical solutions for the field variables. For a domain with an edge-crack, we find that the near-tip strain growth of our model is much slower than the growth of stress, which is the salient feature compared to the inconsistent results of the classical linearized description of the elastic body. Current study can provide a theoretical and computational framework to develop physically meaningful models and examine other coupled multi-physics such as an evolution of complex network of cracks induced by thermal shocks.