Numerical simulations were used to investigate natural radiation and convection interactions in small rooms with
three-dimensional geometry. The opposite vertical walls are heated and cooled, while the other walls are supposed to be fixed.
Governance flow, momentum equations, and radiative conversion are solved using Ansys Fluent CFD. In estimating thermal
terminology, a second-degree wind diagram and a dual solution algorithm are used. The cubic box is filled with air and the flow
is considered protective. Air characteristics are assumed to be constant, except for the difference in density in which a Bosnic
approximation is used. The surface heat model (S2S) is used as the radiation transfer model. The arithmetic field is a square
container Length of the edge = 0.225 m In a surrounding environment at T = 293 K. One of the walls of the case is heated up to
473 K. Note that the radiation from the opposite wall is high, with the improved model. Radiant heat transfer is reduced
