Wetting phase permeability in a partially saturated horizontal fracture
- Sandia National Labs., Albuquerque, NM (United States)
Fractures within geologic media can dominate the hydraulic properties of the system. Therefore, conceptual models used to assess the potential for radio-nuclide migration in unsaturated fractured rock such as that composing Yucca Mountain, Nevada, must be consistent with flow processes in individual fractures. A major obstacle to the understanding and simulation of unsaturated fracture flow is the paucity of physical data on both fracture aperture structure and relative permeability. An experimental procedure is developed for collecting detailed data on aperture and phase structure from a transparent analog fracture. To facilitate understanding of basic processes and provide a basis for development of effective property models, the simplest possible rough-walled fracture is used. Stable phase structures of varying complexity are created within the horizontal analog fracture. Wetting phase permeability is measured under steady-state conditions. A process based model for wetting phase relative permeability is then explored. Contributions of the following processes to reduced wetting phase permeability under unsaturated conditions are considered: reduction in cross-sectional flow area, increased path length, localized flow restriction, and preferential occupation of large apertures by the non-wetting phase.
- Research Organization:
- American Society of Civil Engineers, New York, NY (United States); American Nuclear Society, La Grange Park, IL (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 60940
- Report Number(s):
- CONF-940553--Vol.4
- Country of Publication:
- United States
- Language:
- English
Similar Records
Factors controlling satiated relative permeability in a partially-saturated horizontal fracture
Satiated Relative Permeability of Variable-Aperture Fractures