The Finite element method, which is usuaJly employed to study thermal conduction within soiid components, has been utilized to solve coupled conduction convection and long-wave radiation problems. As an example, the thermal behavior of special building envelope components under transient conditions is investigated, with the aim of establishing the rate of heat transfer due to the difference between the internal and external temperatures and to the absorption of the incoming solar radiation. The components considered in this paper consist of a two-pane glazing system, an open cavity with air circulation, and an opaque wall. Assuming a sinusoidal variation in the absorbed solar radiation, the temperature distribution and the heat transfers are estimated. Comparisons with standard components are illustrated, and the efficiency of the system has been determined as a function of the climatic data.
