Experimental and finite element analysis on thermal conductivity of burnt clay bricks reinforced with fibers

Abstract

Buildings consume more than 30% of primary energy in order to maintain their indoor temperature which varied due to heating and cooling losses. This energy consumption has been increased dramatically through the last decade due to population explosion, more time is spent indoors along with climate changes. Energy efficient building materials are the ultimate requirement and several insulating materials have been developed to minimize the carbon foot prints. Current research work deals with the conversion of conventional terra cotta brick to porous low thermal conductive brick using various organic fibers. Bamboo, jute, coir, sisal and polyester fibers are used in this research work while all having low embodied energy. Water absorption index of fibers and brick, bulk density and porosity of all types of bricks were measured and relationships with water absorption were also established. Reduction in thermal conductivity was observed, using steady state conduction apparatus: upto 18% reduction in thermal conductivity. Reduction in bulk density, thermal conductivity, and increase in water absorption were all attributed to porosity created by burning of fibers. Thermal conductivity was also estimated analytically by using finite element simulation using ANSYS platform, heat flow and temperature at both ends were selected parameters for input, whereas heat flux and temperature gradient were output. The maximum difference between experimental and analytical thermal conductivity was varied up to 7.8%, which verify its applicability.