Effect of Air Flow on Heat Transfer in Walls

Abstract

An analytical model to characterize the air leakage effects on the heat transfer within a permeable one-layered wall is presented. The general solution to the steady-periodic problem is presented. Temperature profiles and heat flux variations within the wall are analyzed. The effect of air flows on heat transmission through the wall are discussed using a parametric analysis. The thermal advantages of intentionally circulating air through building walls—to provide ventilation—are analyzed and discussed. In particular, the thermal performance of dynamic walls integrated in a whole building is analyzed as a function of the infiltration rate and the building thermal load. It is found that the dynamic walls can achieve energy savings of up to 20 percent of total building thermal load.