Nonasymptotic behavior of a common Eulerian approximation for transport in random velocity fields

G. Dagan, Shlomo P Neuman

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

A particular Eulerian approximation which has become popular in recent years derives from the premise that, in mildly fluctuating velocity fields, terms involving the products of fluctuating quantities can be disregarded in comparison to terms which involve only one such quantity. This leads to a non-Fickian low-order approximation for the ensemble mean concentration (C), where the dispersive flux is not proportional to ∇(C), but is given instead by a convolution integral. The spatial moments of (C) based on this approximation are shown to be in conflict with those obtained from a first-order Lagrangian analysis. Explores this apparent contradiction and concludes that the reason lies in the nonasymptotic nature of the Eulerian approximation whereby terms neglected are of the same order as terms retained. -from Authors

Original languageEnglish (US)
Pages (from-to)3249-3256
Number of pages8
JournalWater Resources Research
Volume27
Issue number12
DOIs
StatePublished - 1991
Externally publishedYes

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Lagrangian analysis
Convolution
Fluxes
product
comparison
conflict

ASJC Scopus subject areas

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

Cite this

Nonasymptotic behavior of a common Eulerian approximation for transport in random velocity fields. / Dagan, G.; Neuman, Shlomo P.

In: Water Resources Research, Vol. 27, No. 12, 1991, p. 3249-3256.

Research output: Contribution to journalArticle

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