Transport in Porous Media

, Volume 56, Issue 3, pp 329–350

A Numerical Study of Micro-Heterogeneity Effects on Upscaled Properties of Two-Phase Flow in Porous Media

  • D. B. Das
  • S. M. Hassanizadeh
  • B. E. Rotter
  • B. Ataie-Ashtiani
Article

DOI: 10.1023/B:TIPM.0000026079.44992.fb

Cite this article as:
Das, D.B., Hassanizadeh, S.M., Rotter, B.E. et al. Transport in Porous Media (2004) 56: 329. doi:10.1023/B:TIPM.0000026079.44992.fb

Abstract

Commonly, capillary pressure–saturation–relative permeability (PcSKr) relationships are obtained by means of laboratory experiments carried out on soil samples that are up to 10–12 cm long. In obtaining these relationships, it is implicitly assumed that the soil sample is homogeneous. However, it is well known that even at such scales, some micro-heterogeneities may exist. These heterogeneous regions will have distinct multiphase flow properties and will affect saturation and distribution of wetting and non-wetting phases within the soil sample. This, in turn, may affect the measured two-phase flow relationships. In the present work, numerical simulations have been carried out to investigate how the variations in nature, amount, and distribution of sub-sample scale heterogeneities affect PcSKr relationships for dense non-aqueous phase liquid (DNAPL) and water flow. Fourteen combinations of sand types and heterogeneous patterns have been defined. These include binary combinations of coarse sand imbedded in fine sand and vice versa. The domains size is chosen so that it represents typical laboratory samples used in the measurements of PcSKr curves. Upscaled drainage and imbibition PcSKr relationships for various heterogeneity patterns have been obtained and compared in order to determine the relative significance of the heterogeneity patterns. Our results show that for micro-heterogeneities of the type shown here, the upscaled PcS curve mainly follows the corresponding curve for the background sand. Only irreducible water saturation (in drainage) and residual DNAPL saturation (in imbibition) are affected by the presence and intensity of heterogeneities.

micro-heterogeneity upscaling capillary pressure–saturation–relative permeability relationships DNAPL water 

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • D. B. Das
    • 1
  • S. M. Hassanizadeh
    • 2
  • B. E. Rotter
    • 3
  • B. Ataie-Ashtiani
    • 4
  1. 1.Department of Engineering ScienceThe University of OxfordOxfordUK
  2. 2.Department of Earth SciencesUtrecht UniversityUtrechtThe Netherlands
  3. 3.Institute for Infrastructure and Environment, School of Engineering and ElectronicsEdinburgh UniversityEdinburghUK
  4. 4.Department of Civil EngineeringSharif University of TechnologyTehranIran