STUDY OF CONVECTIVE PHENOMENA INSIDE CAVITIES COUPLED WITH HEAT AND MASS TRANSFERS THROUGH POROUS MEDIA-APPLICATION TO VERTICAL HOLLOW BRICKS - A FIRST APPROACH

Building structures often contain cavities or strips of air. Because o f this, it is difficult to describe the transfer phenomena that are in fact heat transfers (conductive, convective and radiative), as well a s mass transfers through porous media. Numerous studies have dealt wit h each of these transfers separately but few have managed to describe the interrelation between them. This paper represents an initial appro ach to the problem, by attempting to describe the influence of the moi sture level on heat transfers occurring through hollow vertical terra- cotta bricks. A theoretical modeling of exchanges has been carried out in order to determine radiative and convective exchanges coefficients . A mass exchange coefficient has then been deduced. The results obtai ned show a high sensitivity of the heat flux to the moisture level of the surroundings. (C) 1998 Elsevier Science S.A. All rights reserved.