Applying a Radiative Heat Transfer Finite-Volume Methodology to a Geometrically Complex Furnace

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 inhouse 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 tetrahedral or hybrid unstructured grids. Increased accuracy is succeeded with a second-order scheme. The final steady-state solution is obtained with an iterative procedure, based on an explicit second-order accurate in time four-stage Runge-Kutta method and accelerated mainly via parallel processing and an agglomeration multigrid scheme. The proposed solver is assessed against an experimental three-dimensional furnace case, incorporating many of the geometric complexities encountered in industrial furnace systems. The predicted numerical results, regarding the incident wall fluxes, are compared with the available experimental data, revealing a satisfactory agreement and consequently demonstrating the proposed code’s potential to predict accurately radiative heat transfer in complex enclosures.