Abstract
A new three phase equation to explain the effective thermal conductivity of moist rocks has been derived by analyzing data obtained with eighteen kinds of porous rocks at various moisture conditions. The equation is mathematically based on the weighed geometric mean, and it is modified to take into account the effect of porosity.
In the equation derived, the effective thermal conductivity of the porous rocks is expressed as a function of the thermal conductivities of solid, liquid and gas and their volume fractions in the rock. Validity of the equation and degree of the influence of the affecting factors to the effective thermal conductivity of the three phased material have been also discussed.
The equation correlates the experimental data within ±22% in accuracy. When the effective thermal conductivity, porosity and water content of a certain rock at only one condition are known, the effective thermal conductivity of the rock at other various moisture conditions may be estimated using the equation.
