Development and Comparison of Different Model Concepts for Two-Phase Flow in Fractured Porous Media

Fast flow processes of water in fracture-like or tube-like structures within porous media occur in number of engineering applications. One example is given by rainfall induced surface-runoff which fast infiltrates via macropores into the subsurface. Another example is given by tube-like failures in dikes caused by animals or dead roots where water can fast infiltrate or exfiltrate. The classical model concept for two-phase flow in porous media assumes the validity of the Darcy law also in the fracture. On the one hand, this model concept should be extended to account for the fast flow in the 'fractures'. On the other hand, it should be compared to other model concepts such as pipe flow or a double-continuum approach which must be further developed for these purposes. The model concepts will be validated by hillslope and dike experiments. The development of upscaling methods, for example with geostatistical methods, is envisaged.