Modeling of water flow in variably saturated porous media, including flood dikes, is often based on the Richards equation, which neglects the flow of pore air, assuming that it remains at constant atmospheric pressure. However, there is also evidence that the air flow can be important, especially when the connectivity between the pore air and atmospheric air is lost. In such cases a full two-phase air-water flow model should be used. This paper presents numerical simulations of seeepage in dikes based on these two mathematical models. The models were implemented in a general purpose commercial finite element solver FlexPDE. Two boundary problems were considered, corresponding to seepage through dike and overtopping of the dike. In the case of seepage through the dike the two-phase model predicted significantly slower development of the outflow at the inner (landward) slope of the dike as compared to the Richards equation. In the second scenario (overtopping) we observed slower infiltration in the central, unsaturated part of the dike according to the two-phase model.
Authors
Additional information
- Category
- Aktywność konferencyjna
- Type
- publikacja w wydawnictwie zbiorowym recenzowanym (także w materiałach konferencyjnych)
- Language
- angielski
- Publication year
- 2014
