Glass, T.S. Steenhuis and J.-Y. Parlange,
1989
Water Resour. Res. 25 (1989a), pp. 1187-1194
| Highly nonuniform moisture and solute transport in sandy soils has long been noted. A mechanism for nonuniform transport is an instability in the infiltration flow itself, or wetting front instability. When a wetting front becomes unstable, "fingers" form and move down through the vadose zone to the phreatic surface bypassing much of the unsaturated porous medium. In this paper a theoretical framework for wetting-front-instability experimentation is developed through classical dimensional analysis. Relationships between system parameters and initial/boundary conditions and unstable flow field behavior, as characterized by finger width and finger velocity, are derived. The scaling theory of E. E. Miller and R. D. Miller (1956) is used to generalize these relationships to similar porous media with different mean grain sizes and show the effects of coarseness and fluid properties. Other formulations for finger width, derived through linear stability analysis, are examined to arrive at possible functional forms not yielded by dimensional analysis.
Glass and Nicholl, 1996. R.J. Glass and M.J. Nicholl, Physics of gravity fingering of immiscible fluids within porous media: An overview of current understanding and selected complicating factors. Geoderma 70 (1996), pp. 133-163 this issue . Article | PDF (1540 K) | View Record in Scopus | Cited By in Scopus (60)
Glass et al., 1989a. R.J. Glass, T.S. Steenhuis and J.-Y. Parlange, Wetting front instability: 1. Theoretical discussion and dimensional analysis. Water Resour. Res. 25 (1989a), pp. 1187-1194. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (52)
Glass et al., 1989b. R.J. Glass, T.S. Steenhuis and J.-Y. Parlange, Wetting front instability: 2. Experimental determination of relationships between system parameters and two-dimensional unstable flow field behavior in initially dry porous media. Water Resour. Res. 25 (1989b), pp. 1195-1207.
Glass et al., 1989c. R.J. Glass, T.S. Steenhuis and J.-Y. Parlange, Mechanism for finger persistence in homogeneous, unsaturated, porous media: Theory and verification. Soil Sci. 148 (1989c), pp. 60-70.
Glass et al., 1990. R.J. Glass, J. King, S. Cann, N. Bailey, J.-Y. Parlange and T.S. Steenhuis, Wetting front instability in unsaturated porous media: A three-dimensional study. Transp. Porous Media 5 (1990), pp. 247-268.
Glass et al., 1991. R.J. Glass, J.-Y. Parlange and T.S. Steenhuis, Immiscible displacement in porous media: Stability analysis of three-dimensional, axisymmetric disturbances with application to gravity-driven wetting front instability. Water Resour. Res. 27 (1991), pp. 1947-1956. |
