MODELING EQUATIONS FOR TWO-DIMENSIONAL COUPLED HEAT, FLUID AND SOLUTE TRANSPORT IN VARIABLY-SATURATED, VARIABLY-FROZEN SOILS

Authors: NIEBER, JOHN - UNIVERSITY OF MINNESOTA; FRIEDEL, MIKE - UNIVERSITY OF MINNESOTA; Sharratt, Brenton

Submitted to: Seasonally Frozen Soils Symposium
Publication Type: Proceedings
Publication Acceptance Date: 6/12/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary: Two computer simulations were developed previous to this study that mimic heat, water, and chemical movement in soils that are subject to freezing. Both simulations, however, account for only vertical, or one-dimensional flow processes. We developed a simulation that mimics heat, water, and chemical movement both vertically and horizontally in a seasonally frozen soil. This new technology will allow scientists and land managers to assess the fate of chemicals in ridge tillage systems and in depressional landscapes during the entire year in cold regions. The technology can also be used by chemicals representatives in recommending where chemicals should be placed on ridges or landscapes to minimize downward movement of chemicals. The EPA also will benefit from the development of this simulation in assessing off-site movement of contaminants in permanently-frozen soils.

Technical Abstract: The governing equations for the time-dependent and multidimensional coupled flow of water and air, and transport of heat and aqueous phase solutes are presented. The boundary conditions appropriate for the application of the governing equations to a realistic field problem are illustrated. Numerical solution procedures, including the temporal and spatial discretization methods, nonlinear iterative methods and matrix equation solution methods are discussed.