Steady-state heat flow through hollow clay bricks

Clay bricks are commonly used for building wall. One of the functions of a wall is to create a habitable internal environment, such as enabling internal temperature to be controlled at a human comfort level (~24°C) which is lower than the outside temperature for hot and humid climate countries. Thus, it is important for clay bricks to minimize heat flow into the building to reduce the energy consumption by air-conditioning system. The aim of this paper is to investigate the reduction of heat flow through hollow clay bricks relative to solid bricks. Finite element method was used to simulate steady-state heat transfer through solid and hollow clay bricks. Several arrangements of cavities filled with air, wool and expanded foam were simulated. It was found that the effective thermal conductivity reached almost a constant when the void volume and reduction in cross-sectional area exceeds 10%. Generally, heat transfer through hollow clay brick is expected to be significantly lower than the solid clay brick. It can be concluded that building wall made from hollow clay bricks could reduce the energy consumption by its air conditioning system. Future work is on the transient heat flow analysis and evaluation of mechanical properties of hollow clay bricks.