Numerical Analysis of Variation of Saturation and Moisture Transport at the Vicinity of a Heat Source

摘要

Heat and mass transfers in unsaturated porous media have not been thoroughly investigated in previous studies as most of them assumed that conduction is the only heat transfer mechanism in soil, neglecting convection and phase change while considering constant soil thermal properties. Thermal gradient from a heat source reduces moisture content of the surrounding soil. The dry-out process along with coupled heat and mass transfer can directly affect thermo-hydro-mechanical behavior of soil which has not been previously investigated in the literature. The aim of this study is to evaluate the effect of coupled heat and mass transfer in unsaturated soil and assess the moisture content variation in proximity of a heat source. Hence, a non-equilibrium multiphase flow model is adopted to numerically simulate heat and mass transfer. Different scenarios are defined by changing initial moisture content and heat flux. Results show significant dependency of soil moisture variation to initial conditions.