A theoretical model for estimating the thermal conductivity of granular geomaterials with low porosity

Abstract

The thermal conductivity has an important influence on the geotechnical and geoenvironmental engineering. Most existing thermal conductivity models appear to estimate the thermal conductivity of soils samples with large porosity, few of them were proposed to model the thermal conductivity of soil samples with low porosity. In this study, a theoretical model was proposed to estimate the thermal conductivity of unsaturated granular geomaterials with low porosity. Two parameters (i.e., ζ and β) were introduced. The parameter ζ can be applied to control porosity and solid particle shape, while the parameter β can be used to control water content. Mathematical comparison showed that the proposed thermal conductivity model fell within the Wiener bounds. The new model and five thermal conductivity models were evaluated with experimental data, showing that the new model accurately estimates the relationship between thermal conductivity and saturation for granular geomaterials with low porosity.