Natural convection in a cavity with a window

Combined natural convection and radiation in a rectangular cavity has been studied numerically. One wall of the cavity is transparent, permitting radiation exchanges between the cavity and the surroundings and/or the sun; that wall also exchanges heat by convection from its external surface to the surroundings. The opposite wall is isothermal, being heated either by solar radiation or independently. The other two walls are adiabatic: convection and radiation there are balanced, so that there is no heat transfer through those walls. A two band radiation model has been employed. The equations of motion and energy are solved by finite difference methods. Coupled to them are the radiative flux boundary conditions; they and their method of incorporation into the solution procedure are described.