IUTAM Symposium on Turbulent Mixing and Combustion
Volume 70 of the series Fluid Mechanics and Its Applications pp 181199
Challenges in Modeling Scalars in Turbulence and LES
 C. MeneveauAffiliated withDepartment of Mechanical Engineering, Johns Hopkins UniversityCenter for Environmental & Applied Fluid Mechanics
 , H. S. KangAffiliated withDepartment of Mechanical Engineering, Johns Hopkins University
 , F. CharletteAffiliated withDepartment of Mechanical Engineering, Johns Hopkins UniversityInstitute Français du Pétrole
 , J. AverillAffiliated withDepartment of Mechanical Engineering, Johns Hopkins UniversityNational Institute of Standards & Technology
 , O. KnioAffiliated withDepartment of Mechanical Engineering, Johns Hopkins UniversityCenter for Environmental & Applied Fluid Mechanics
 , D. VeynanteAffiliated withLaboratoire EM2C, Ecole Centrale
Abstract
This paper discusses three interrelated aspects of modeling scalar transport, mixing and combustion, in the context of largeeddy simulations (LES). In terms of passive scalar modeling, we find from heated wake measurements that whereas the kinetic energy dissipation tensor tends towards isotropy at small scales, in the presence of a mean scalar gradient the SGS scalar variance dissipation remains anisotropic independent of filter scale. The eddydiffusion model predicts isotropic behavior, whereas the nonlinear model reproduces the correct trends, but overestimates the level of scalar dissipation anisotropy. The results provide some support for mixed models. Applications of dynamic models are also discussed. Initial tests on nonbuoyant jet flows show that the constantcoefficient Smagorinsky model generates an entirely laminar jet, whereas the Lagrangian dynamic model yields very good results without the need to tune the model coefficient. In the context of applying the dynamic model to premixed combustion, or other physical processes with large scaleseparations, we show that the dynamic determination of unknown scaling exponents is a more promising approach than dynamic evaluation of model coefficients.
Keywords
LES passive scalar anisotropy modeling scale separation dynamic model premixed combustion Title
 Challenges in Modeling Scalars in Turbulence and LES
 Book Title
 IUTAM Symposium on Turbulent Mixing and Combustion
 Book Subtitle
 Proceedings of the IUTAM Symposium held in Kingston, Ontario, Canada, 3–6 June 2001
 Book Part
 Session 3
 Pages
 pp 181199
 Copyright
 2002
 DOI
 10.1007/9789401719988_15
 Print ISBN
 9789048160747
 Online ISBN
 9789401719988
 Series Title
 Fluid Mechanics and Its Applications
 Series Volume
 70
 Series ISSN
 09265112
 Publisher
 Springer Netherlands
 Copyright Holder
 Springer Science+Business Media Dordrecht
 Additional Links
 Topics
 Keywords

 LES
 passive scalar anisotropy
 modeling
 scale separation
 dynamic model
 premixed combustion
 Industry Sectors
 eBook Packages
 Editors

 A. Pollard ^{(2)}
 S. Candel ^{(3)}
 Editor Affiliations

 2. Department of Mechanical Engineering, Queen’s University
 3. Ecole Centrale Paris, EM2C, CNRS
 Authors

 C. Meneveau ^{(4)} ^{(5)}
 H. S. Kang ^{(4)}
 F. Charlette ^{(4)} ^{(6)}
 J. Averill ^{(4)} ^{(7)}
 O. Knio ^{(4)} ^{(5)}
 D. Veynante ^{(8)}
 Author Affiliations

 4. Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
 5. Center for Environmental & Applied Fluid Mechanics, USA
 6. Institute Français du Pétrole, RueilMalmaison, France
 7. National Institute of Standards & Technology, Gaithersburg, USA
 8. Laboratoire EM2C, Ecole Centrale, Paris, France
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