Natural Convection and Surface Radiation in a Cavity with a Partially Heated Rectangular Block

This paper uses a combination of the discrete ordinate method and finite volume method to numerically study surface radiation and natural convection in a square cavity with a partially heated inner rectangular block. The system under investigation consists of an air-filled cavity, with symmetrical cooling provided by vertical sidewalls at a cold temperature \({\text{T}}_{{\text{C}}}\) . The study aims to analyze the hydrodynamic and thermal behavior of the fluid, as well as the convective and radiative heat transfers, by varying the Rayleigh numbers and surface emissivities. To carry out the research, a custom CFD code developed in FORTRAN is utilized. The findings reveal that the presence of surface radiation enhances the flow intensity within the cavity.