Modeling Thermal Conductivity Dryout Curves from Soil-Water Characteristic Curves

摘要

A new approach is proposed for modeling thermal conductivity dryout curves (TCDCs) using measurements of soil-water characteristic curves (SWCCs) for coarse-grained unsaturated soils. The approach is based on observation of similitude between a bimodal formulation of the SWCC in the form S(ψ) and the TCDC in the form λ(ψ). The model may be used in either an empirical curve-fitting capacity to best-fit measured "thermal conductivity data or in a predictive capacity to estimate a TCDC from a measured SWCC. Applying the model in a curve-fitting capacity facilitates numerical modeling of heat transfer problems by providing a continuous function for the TCDC. Applying the model in a predictive capacity potentially has broad applications because the SWCC is readily measured or estimated in practice, but the TCDC is not. Performance and characteristics of the model are evaluated by comparison with SWCCs and TCDCs measured for a suite of sands. Predicted thermal conductivity is within 10% of measured values over the complete range of saturation.