On the role of conditional averages in turbulence theory.

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

It is shown that conditional averages in the form of expected values of functions of the velocity at an arbitrary point given the velocities at a finite number of distinct points, appear naturally in certain types of turbulence theories and that the closure problems in such theories ultimately reduce to the approximation of these averages. Two exemplary theories are considered. The first is characteristic of turbulence models formulated in terms of probability density functions whereas the second is related to the derivation of optimal algorithms for the numerical integration of the turbulent Navier-Stokes equations at large Reynolds numbers. Some mathematical properties of conditional expected values, including relations between conditional and unconditional second order tensor moments and results for the special case of isotropic turbulence are also presented. (A)

Original languageEnglish (US)
Journal[No source information available]
StatePublished - Jan 1 1977
Externally publishedYes

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Turbulence
Turbulence models
Probability density function
Navier Stokes equations
Tensors
Reynolds number

ASJC Scopus subject areas

  • Engineering(all)

Cite this

On the role of conditional averages in turbulence theory. / Adrian, Ronald.

In: [No source information available], 01.01.1977.

Research output: Contribution to journalArticle

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