Computations of Radiative Heat Transfer inside Buildings

Abstract

The present conference contribution is devoted to the application of the theoretical model of radiative heat transfer formulated in our first conference contribution entitled “General Formalism for the Computation of Radiative Heat Transfer”. In that preceding contribution, a general model for radiative heat transfer in inner spaces of buildings has been developed and the present contribution illustrates its application to a simple room. The room consists of two surfaces, namely, the heated circular floor and arched ceiling (cupola). The processing of this two-surface room has been accomplished by two methods, i.e. by means of view factors along with radiosities and alternatively by means of mutual emissivities. The model based on radiosity is quite general and is not restricted to a certain number of surfaces whereas the second model based on mutual emissivities is restricted only to two-surface rooms. These two alternative procedures offer the comparison of their computational effectiveness. The behaviour of the radiative heat flow in closed two-surface envelopes is subjected to analysis and numerical computations have shown that the total radiative heat flows tend to reach the compensation state in which the positive flow of the warm surface is compensated by the negative flow of the cold surface.