Moisture and Temperature Response of Structural and Lithology based Thermophysical and Energy Saving Traits of Limestone using Experimental and Least-Square Fitting Methods

Abstract

Thermophysical analysis of the crustal rocks is important for heat transfer determination and insulation purposes to save energy in buildings. In the presented work, thermophysical properties of four limestones were investigated in dry and moist state under ambient conditions by using a transient plane source method. A thermal constant analyzer was used to raise the sample temperature and to measure the thermal properties in the temperature range of 300 K to 433 K. Thermal conductivity and diffusivity were measured by developing a linear relationship between temperature response of TPS (transient plane source) sensor and dimensionless time function through least-square fitting method. The experimental observations and predicted thermal conductivity of samples have shown that in-situ observations are important to determine the thermal properties accurately. The effect of temperature on thermal properties of limestone was defined by considering the chemical composition of the samples and associated heat transfer mechanism. Both thermal conductivity and diffusivity of limestone decreased while specific heat capacity increased with a rise in temperature. The overall findings indicate that the spinoff of this research is useful in studying the reliance of thermophysical properties of rocks on their structures and lithology.