Cohesive Fracture Growth in a Thermoelastic Bi-material Medium

The paper presents a fully-coupled numerical model for the analysis of fracture initiation and propagation in a two dimensional non-homogeneous elastic medium driven by mechanical loads and transient thermal fields. Cohesive crack behaviour is assumed for the solid. The solution of the coupled problem is obtained by using the finite element method without using special approximation techniques nor interface elements. Evolution of the process zone results in continuous changes of the domain topology. This is accounted for by updating the boundary geometry and successive remeshing of the domain. Optimality of the shape of the finite elements generated is controlled and the mesh density is adjusted adaptively on the basis of an error estimator. Two numerical applications are presented, which demonstrate the effectiveness of the proposed procedure. In the first, comparison is made with a laboratory experiment, whereas the second handles a problem with crack path completely unknown.