In the recent years, silicon carbide (SiC) is emerging as a main material in the semiconductor industry thanks to its outstanding properties. The production method is known as Physical Vapor Transport (PVT), nonetheless, the setup configuration does not allow to get information in-situ. Therefore, computational simulations became the main approach to control and predict the PVT parameters, especially using Finite Element Method (FEM) modelling. Although the construction of a FEM model for modelling a growth process could be complex due to the physics involved. This master thesis deals with the validation of different algorithm to account heat transfer by radiation physics. COMSOL Multiphysics is a FEM software which has different algorithms (direct area integration, hemicube and ray shooting) to describe surface-to-surface radiation. These algorithms are tested and validate to determine their accuracy in a simple and initial PVT model, which could be the basis for more complex models.