Natural element method study of combined natural convective and radiative heat transfer in irregular-shaped mediums with radiative properties

Numerical analysis of combined heat transfer in enclosures is of importance in thermal science. Among numerical approaches for the analysis of combined heat transfer, Natural Element Method (NEM) is well known as an efficient meshless technique, whose theory mainly based on natural Galerkin neighbors. The triangular medium is subjected to the simultaneous effect of natural convection fluid flow, conduction and radiation inside an absorbing, emitting, non-scattering and semi-transparent enclosure. Then, the concept of NEM is implemented for the discretization of mathematical governing equations within computational field. For radiation analysis, both P1 and Discrete Ordinate Method (DOM) are employed to determine the solution of Radiative Transfer Equation (RTE) through iterative procedure, which ultimately converges to final solutions that are then compared with analytical and numerical studies found in the literature. From the results, Natural Element Method shows its good performance on numerical heat transfer analysis of fluid flow problems.