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new time scale based k-epsilon model for near-wall turbulenceA k-epsilon model is proposed for wall bonded turbulent flows. In this model, the eddy viscosity is characterized by a turbulent velocity scale and a turbulent time scale. The time scale is bounded from below by the Kolmogorov time scale. The dissipation equation is reformulated using this time scale and no singularity exists at the wall. The damping function used in the eddy viscosity is chosen to be a function of R(sub y) = (k(sup 1/2)y)/v instead of y(+). Hence, the model could be used for flows with separation. The model constants used are the same as in the high Reynolds number standard k-epsilon model. Thus, the proposed model will be also suitable for flows far from the wall. Turbulent channel flows at different Reynolds numbers and turbulent boundary layer flows with and without pressure gradient are calculated. Results show that the model predictions are in good agreement with direct numerical simulation and experimental data.
Document ID
19930057912
Document Type
Reprint (Version printed in journal)
Authors
Yang, Z.
(NASA Lewis Research Center Cleveland, OH, United States)
Shih, T. H.
(NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 16, 2013
Publication Date
July 1, 1993
Publication Information
Publication: AIAA Journal
Volume: 31
Issue: 7
ISSN: 0001-1452
Subject Category
FLUID MECHANICS AND HEAT TRANSFER
Distribution Limits
Public
Copyright
Other