Fully coupled formulation of surface flow with 2-phase subsurface flow forhydrological simulation

With the aim of realizing a surface-subsurface-coupled fluid flow simulatio n, the authors discuss surface flow models that can be used in the framewor k of the 2-phase subsurface numerical simulation system. In this paper, thr ee surface flow models, i.e., a kinematic wave model (KW), a diffusion wave model (DW), and a linearized diffusion wave model (LDW), are explained by approximating the momentum equation, and are transformed into a set of nonl inear functions which can be solved simultaneously with the 2-phase subsurf ace flow. By incorporating these into a 2-phase numerical simulation system , comparison studies are carried out using experimental data and a held sca le model. So far as the results of the study are concerned, it is concluded that the DW model gives reasonable performance for any case, the LDW model provides mostly identical results with the DW model with some restrictions , while the KW model is not applicable for the physical modelling of contin uous flow through multiple slopes with different angles. Copyright (C) 2000 John Wiley & Sons, Ltd.