On the Coupling Between Channel Level and Surface Ground Water Flows

This paper is devoted to a mathematical analysis of some general models of mass transport and other coupled physical processes developed in simultaneous flows of surface, soil and ground waters. Such models are widely used for forecasting (numerical simu1 lation) of a hydrological cycle for concrete territories. The mathematical models that proved a more realistic approach are obtained by combining several of mathematical models for local processes. The water exchange models take into account the following factors: water flows in confined and unconfined aquifers, vertical moisture migration with allowing earth surface evaporation, open-channel flow simulated by one-dimensional hydraulic equations,transport of contamination, etc. These models may have different levels of sophistication. We illustrate the type of mathematical singularities which may appear by considering a simple model on the coupling of a surface flow of surface and ground waters with the flow of a line channel or river.