OpenFOAM was used to numerically investigate heat conduction in heterogeneous media. The main advantage of this platform is that it offers an open flexible interface with great convenience for mesh generation and solver modification. Cases of 1D and 2D heat conduction problems in media with different levels of heterogeneity were considered to check the performance of OpenFOAM. The results were compared with references and other commercial software and showed good accuracy. Note that all of the processes, including the mesh generation, numerical simulation, and post-processing, relied on free open-source codes. (C) 2018 Elsevier Ltd. All rights reserved.