A Numerical Study of the Effect of a Below-Window Convective Heater on the Heat Transfer Rate from a Cold Recessed Window

An approximate numerical model of convective heat transfer to a window below which is mounted a natural convective heater has been used to study how the relative temperature of the heater affects the convective heat transfer rate to the window and the flow in the room. The heater and the window are represented by plane isothermal sections on the wall surface, the window section being recessed into the wall and colder than the room air far from the wall and the heater section being flush with the wall and hotter than the room air far from the wall. The width of the heater is greater than that of the window and the flow, which is assumed to be steady and laminar, is therefore three-dimensional. The numerical results which were obtained using a commercial cfd code show the effect of the Rayleigh number and of the dimensionless heater temperature on the window Nusselt number. The conditions under which the downward flow from the window is diverted upward by the flow from the heater have also been investigated.