ABSTRACT
We present analyses of unsaturated and partially saturated flow in porous media, related to soil infiltration problems and to beach groundwater hydrodynamics.
We focus on the effects of heterogeneities (soil stratification, sloping interfaces, beach drainage systems) and on the effects of time variability in soil hydrology (time variable infiltration and ponding) and beach hydrodynamics (fluctuating water tables due to sea level oscillations at various frequencies, including tidal frequencies).
The study is conducted using numerical modeling approaches, and in some cases, quasi-analytical methods. Both unsaturated and partially saturated porous systems are analyzed. The emphasis is on the role of capillary effects in the unsaturated zone, and on the competition between gravity and capillarity effects, in the presence of forced oscillations and/or in the presence of geometric heterogeneity (capillary barriers).
The results of these investigations, in the case of oscillatory flow systems, will serve to back up an ongoing laboratory experiment of groundwater flow in a sandy beach represented in vertical cross-section (cross-shore). The theoretical and numerical modeling will be used to experiment numerically (beyond the conditions of the lab experiment) the geometric effects of beach slope 1 , beach stratification, and beach drainage systems 2 . The effect of stratification will also be examined in the case of rainfall infiltration. The capillary barrier effect that may occur in several cases of interest, both in soil hydrology and in beach hydrodynamics.
