Fabrication of Thermal Probes for Estimation of Soil Thermal Resistivity

摘要

Thermal properties of soils are of great importance in view of the subsurface transmission of heated fluids or high electric currents. For these situations, it is essential to estimate the resistance offered by the soil mass in dissipating the heat generated through it. It has been demonstrated by researchers that soil thermal resistivity is a complex phenomenon that depends on various parameters such as type of soil, particle size distribution, and compaction characteristics. This poses a problem in estimating soil thermal resistivity using existing empirical and mathematical models. This calls for fabrication of a laboratory thermal probe that can be used to measure soil thermal resistivity of a soil sample either remolded to the in situ state of the soil or brought to the laboratory in an undisturbed form. However, as the laboratory sample would not represent the actual in situ state of the soil mass, efforts must be made to measure the soil thermal resistivity with the help of a field thermal probe. These probes, which work on the principle of the transient method, are found to be quite effective in measuring soil thermal resistivity.