Numerical solutions of moment equations for flow in heterogeneous composite aquifers

C Larrabee Winter, Daniel M. Tartakovsky, Alberto Guadagnini

Research output: Contribution to journalArticle

41 Citations (Scopus)

Abstract

We analyze flow in heterogeneous media composed of multiple materials whose hydraulic properties and geometries are uncertain. Our analysis relies On the composite media theory of Winter and Tartakovsky [2000, 2002], which allows one to derive and solve moment equations even when the medium is highly heterogeneous. We use numerical solutions of Darcy flows through a representative composite medium to investigate the robustness of perturbation approximations in porous medium with total log conductivity variances as high as 20. We also investigate the relative importance of the two sources of uncertainty in composite media, material properties, and geometry. In our examples the uncertain geometry by itself captures the main features of the mean head estimated by the full composite model even when the within-material conductivities are deterministic. However, neglecting randomness within materials leads to head variance estimates that are qualitatively and quantitatively wrong. We Compare the composite media approach to approximations that replace statistically inhomogeneous conductivity fields with pseudohomogeneous random fields with deterministic trends. We demonstrate that models with a deterministic trend can be expected to give a poor estimate of the statistics of head.

Original languageEnglish (US)
Pages (from-to)131-138
Number of pages8
JournalWater Resources Research
Volume38
Issue number5
StatePublished - May 2002
Externally publishedYes

Fingerprint

Aquifers
aquifers
aquifer
Composite materials
conductivity
geometry
Geometry
porous media
heterogeneous medium
hydraulic property
fluid mechanics
uncertainty
statistics
Porous materials
porous medium
Materials properties
perturbation
Hydraulics
Statistics
winter

Keywords

  • Domain decomposition
  • Random
  • Stochastic
  • Uncertainty

ASJC Scopus subject areas

  • Environmental Science(all)
  • Environmental Chemistry
  • Aquatic Science
  • Water Science and Technology

Cite this

Numerical solutions of moment equations for flow in heterogeneous composite aquifers. / Winter, C Larrabee; Tartakovsky, Daniel M.; Guadagnini, Alberto.

In: Water Resources Research, Vol. 38, No. 5, 05.2002, p. 131-138.

Research output: Contribution to journalArticle

Winter, C Larrabee ; Tartakovsky, Daniel M. ; Guadagnini, Alberto. / Numerical solutions of moment equations for flow in heterogeneous composite aquifers. In: Water Resources Research. 2002 ; Vol. 38, No. 5. pp. 131-138.
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