Document Type

Article

Publication Date

2007

Journal or Book Title

Physics of Fluids

Volume

19

First Page

085102-1

Last Page

085102-19

DOI

10.1063/1.2757699

Abstract

The multi-environment conditional probability-density-function (MECPDF) approach for modeling extinction and re-ignition in turbulent nonpremixed reacting flows in analyzed. A unique derivation of the model is given, which makes use of numerical Gaussian quadrature in addition to physical assumptions. The new derivation offers insight into the physical meaning of model terms and offers a more rigorous method for model validation. The assumptions required to close the dissipation terms are validated term by term using data from direct numerical simulations of an inert and a reacting scalar in decaying isotropic turbulence. Results show convergence of the numerical quadrature with an increasing number of quadrature points. Also, good agreement is shown for the physical model assumptions required to close the mixed dissipation and the progress-variable dissipation terms. The MECPDF methods is also demonstrated to offer the flexibility to incorporate either micromixing or otherwise more sophisticated models for the mixing between regions of the flow that exhibit differing degrees of extinction.

Comments

This article is from Physics of Fluids 19 (2007): 085102-1 - 085102-19, doi: 10.1063/1.2757699.

Copyright Owner

American Institute of Physics

Language

en

File Format

application/pdf

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