Summarization: Considering that radiative heat transfer is encountered in many engineering and industrial applications, significant efforts have been applied during the last decades for the development of relevant numerical methodologies. In this study, such an in-house academic radiative heat transfer method is presented in brief, whereas it is evaluated against a geometrically complex furnace. The proposed solver depends on the time-dependent RTE (Radiative Transfer Equation) aiming to predict radiative heat transfer in general enclosures through absorbing, emitting, and either isotropically or anisotropically scattering gray media. Spatial discretization is obtained with a node-centered finite-volume method on three-dimensional tetrahedr...