Heat Transfer in Soil-Water-Ice Systems

The finite element method has an excellent solution capability for problems requiring transient temperature distribution under time-dependent temperature initial and boundary conditions. Some exceptional features in handling are: space variations of temperature-dependent material properties, irregular boundary geometries of problem regions, temperature and heat flux boundary conditions at any point in the problem region, and freedom in varying the size of the finite discretization within the problem region. This paper presents a general computer-oriented solution technique for geotechnical problems of heat conduction, including the effect of latent heat generation and absorption. A variational principle is applied for initial boundary value problems of unsteady heat flow, and the finite elements method is used to generate approximate solutions to plane and axisymmetric problems. Variation in physical and thermal properties of materials with both temperature and space, and functional relationships between the amount of water frozen and the temperature are taken into account automatically during the process of heat conduction.