Steady-state heat transfer in microcracked media

Material behaviour is often affected by the heterogeneities existing at the microscopic level. Especially the presence of cracks, voids, etc collectively known as defects, can play a major role in their overall response. Homogenization can be used to study the influence of these heterogeneities and also to estimate the effective properties of a given material. Several research works have been dedicated to determining the elastic behaviour of microcracked media. Yet, thermal properties are not investigated as much. Moreover, the question of unilateral effect (opening/closing of cracks) still remains an important issue. So, this paper aims to provide the effective thermal conductivity of 2D microcracked media with arbitrarily orientated cracks, either open or closed. With the help of Eshelby-like approach, homogenization schemes (dilute and Mori-Tanaka) and bounds (Ponte Castañeda-Willis) are developed to provide the closed-form expressions. In addition, these results are compared to numerical simulations performed based on finite element modelling.