Abstract
This study investigated the thermophysical properties of moist and salt crystallized fired clay bricks for energy saving perspective. A transient plane source technique was used to study these properties under ambient conditions. Measurements were done by impregnating the brick samples for 10 days with NaCl solutions of known concentrations (0-5 M). Then, the moist-salt crystallized samples were lyophilized at - 50 degrees C for 6 h to grow NaCl crystals. The pore structure, chemical composition and mineral content of the brick samples were determined using SEM-EDS and X-ray diffraction techniques. Physical properties of the brick samples were studied using the standards of the American Society of Testing and Materials. The response of the sample mass, moisture content/%, thermal conductivity, thermal diffusivity and specific heat capacity of moist and NaCl saturated brick samples to NaCl saturation period were also investigated. After freeze-drying of samples, the results confirmed that NaCl crystallization increases with an increase in molarity of NaCl solution in bricks. NaCl crystallization brought a sharp increase in the thermal response and a decrease in the thermal insulation of the brick samples. These trends were described using suitable linear fit equations to assess the thermal performance of the impregnated fired clay bricks.