Equations of frost propagation in unsaturated porous media

✍ Scribed by J.M. Menot

• Publisher: Elsevier Science
• Year: 1979
• Tongue: English
• Weight: 352 KB
• Volume: 13
• Category: Article
• ISSN: 0013-7952
• DOI: 10.1016/0013-7952(79)90024-3

✦ Synopsis

The equations of soil freezing are established where the soil is partially water-saturated, i.e., when it contains air. We choose a macroscopic viewpoint, using leveled parameters (averages on a "small" volume surrounding the considered point). We assume that water can exist at a temperature below 0°C. Mechanical energy (kinetic energy and power of inner forces) is neglected with respect to thermal energy; radiation is also neglected. The establishment of the equations is based upon the expression (1) of the mass and energy conservation laws;and (2) of constitutive laws such as Fourier's law, Darcy's law, the curve of capillary pressure in terms of the saturation degree, etc. We obtain a system of nonlinear partial differential equations with a free surface; the unknowns are the temperature, the saturation degree and the water pressure at each point and at each time ; these unknowns are coupled in the differential equations.