Thermal Conductivity of Quartz Sands by Thermo-Time Domain Reflectometry Probe and Model Prediction

Thermal conductivity of sand–kaolin clay mixtures

“…In Figure 10(a), it is found that the Zhang et al (2015) model showed a very good agreement with the experimental data, while other models exhibited an obvious bias of underestimating the thermal conductivity of mixtures. This is because the effect of high quartz content on soil thermal conductivity was taken into account only in the Zhang et al (2015) model. The difference between measured and predicted results from the Chen (2008) model at high moisture contents might be due to the underestimation of the thermal conductivity of solid.…”

“…It shows a relatively high prediction accuracy for sands or sandy soils (Zhang et al, 2015). Zhang et al (2015) model Zhang et al (2015) measured the thermal conductivities of three sands with an extremely high quartz content by a thermo-TDR probe and a modified Cote and Konrad (2005) model in order to account for the high quartz content effect on soil thermal conductivity. The formula remained the same, but the model parameters were modified as 8·12 W/(m K) for c, 3·18 W/(m K) for h and 6·0 for W/(m K) for quartz sands.…”

“…In terms of soil thermal conductivity prediction, most attempts were made to develop a thermal conductivity model based on empirical fits to experimental data of natural soils (Chen, 2008;Cote and Konrad, 2005;Donazzi et al, 1979;Gangadhara Rao and Singh, 1999;Johansen, 1977;Lu et al, 2007;Kersten, 1949;Zhang et al, 2015). For example, Kersten (1949) performed a series of laboratory experiments to measure the thermal conductivity of 19 different types of soils, and established empirical relationships between thermal conductivity and moisture content and dry density.…”

“…Chen (2008) presented a thermal conductivity model for sands based on the laboratory experiments on four different sands. Zhang et al (2015) used a new thermo-TDR probe to measure the thermal conductivity of three quartz sands, and proposed an improved thermal conductivity model for quartz sands.…”

“…The effect of clay content on thermal conductivity of mixtures was analysed and discussed. Then, five alternative soil thermal conductivity models (Chen, 2008;Cote and Konrad, 2005;Johansen, 1977;Lu et al, 2007;Zhang et al, 2015) were selected to predict the thermal conductivity of the sand-kaolin clay mixtures, and they were compared with the experimental results. The Cote and Konrad (2005) model and the Lu et al (2007) model were also improved to consider the continuous change in thermal conductivity of mixtures as the clay content varied.…”