Modeling of Heat Transfer in a Habitat Built in Local Materials in Dry Tropical Climate

A numerical modeling of heat transfer in a habitat whose walls are in local materials (compressed earth blocks) is presented. The transfer equations based on the nodal method are solved by an implicit finite difference method and the Gauss algorithm coupled to an iterative procedure. It was analyzed the influence of the rate of air exchange, the thickness of the walls and the nature of the materials of which they are composed on the spatio-temporal distributions of the temperature of the air inside the habitat and those of its walls. The results show that the temperature inside habitats whose walls are made of local materials (earthen materials) is lower than that of modern habitats (cement blocks). The increase in the thickness of the walls contributes to a better thermal inertia of the habitat by improving the decrement factor and the time lag difference between the inside and the outside. Also, over-ventilation of a habitat with high inertia has a negative impact on its performance during the hottest periods.