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A Comparative Study of Turbulence Models Performance for Turbulent Flow in a Planar Asymmetric Diffuser

Authors: Samy M. El-Behery, Mofreh H. Hamed

Abstract:

This paper presents a computational study of the separated flow in a planer asymmetric diffuser. The steady RANS equations for turbulent incompressible fluid flow and six turbulence closures are used in the present study. The commercial software code, FLUENT 6.3.26, was used for solving the set of governing equations using various turbulence models. Five of the used turbulence models are available directly in the code while the v2-f turbulence model was implemented via User Defined Scalars (UDS) and User Defined Functions (UDF). A series of computational analysis is performed to assess the performance of turbulence models at different grid density. The results show that the standard k-ω, SST k-ω and v2-f models clearly performed better than other models when an adverse pressure gradient was present. The RSM model shows an acceptable agreement with the velocity and turbulent kinetic energy profiles but it failed to predict the location of separation and attachment points. The standard k-ε and the low-Re k- ε delivered very poor results.

Keywords: Turbulence models, turbulent flow, wall functions, separation, reattachment, diffuser.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1079104

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References:


[1] Wikipedia, "Computational fluid dynamics
[online]", Available at http://en.wikipedia.org/wiki /Computational_ fluid_dynamics,
[accessed Dec. 20, 2008].
[2] Bradshaw P., "Understanding and predictions of turbulent flow - 1996", Int. J. Heat and Fluid Flow, Vol. 18, 1997, pp. 45-54.
[3] Anderson D. A. and Tannehill, J. C. and Pletcher, R. H., "Computational Fluid Mechanics and Heat Transfer", Heimsphere Publishing Corporation, 1984.
[4] http://www.cfd-online.com/Wiki/ Turbulence _ modeling
[accessed Dec. 20, 2008].
[5] Versteeg H. K. and Malalasekera W., "An introduction to computational fluid dynamics, the finite volume method", Longman group Ltd, 1998.
[6] Launder B. E. and Spalding D. P., "The numerical computation of turbulent flows", Computer Methods in Applied Mechanics and Engineering, Vol. 3, 1974, pp. 269-289.
[7] Launder B. E. and Sharma B. I., "Application of the energy-dissipation model of turbulence to the calculation of flow near a spinning disc", Letters in Heat and Mass Transfer, Vol. 1, 1974, pp. 131-138.
[8] Yakhot, V. and Smith, L. M., "The Renormalization Group, the Epsilon- Expansion and Derivation of Turbulence Models", J. Scientific Computing, Vol. 7, 1992, pp. 35-51.
[9] Wilcox D. C., "Turbulence Modeling for CFD", DCW Industries, La Canada, California, 1998.
[10] Menter F. R., "Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications", AIAA Journal, Vol. 32, 1994, pp. 1598- 1605.
[11] Durbin P. A., "Near-wall turbulence closure modeling without damping functions", Theoretical and Computational. Fluid Dynamics, Vol. 3, 1991, pp. 1-13.
[12] Launder B. E. and Spalding D. B., "Mathematical Models of Turbulence", Lectures Notes, Imperial College of Science and Technology, London, England, 1972.
[13] Patel V. C., Rodi W. and Scheuerer G., "Turbulence models for Nearwall and low Reynolds number flows: a review", AIAA J., Vol. 23, 1985, pp. 1308-1318.
[14] Fluent, "User-s Guide Fluent 6.3.26", Fluent Incorporated, Lebanon, NH, 2006.
[15] Lien F-S and Kalitzin G, "Computations of transonic flow with the v2-f turbulence model", Int. J. Heat Fluid Flow, Vol. 22, 2001, pp. 5361.
[16] Kim J-Y, Ghajar A. J., Clementang and Foutch G. L., "Comparison of near-wall treatment methods for high Reynolds number backward-facing step flow", Int. J. Computational fluid dynamics, Vol. 19, 2005, pp. 493- 500.
[17] Obi, S., Aoki, K., and Masuda, S., "Experimental and Computational Study of Turbulent Separating Flow in an Asymmetric Plane Diffuser," Ninth Symposium on Turbulent Shear Flows, Kyoto, Japan, August 16- 19, pp. 305-1 to 305-4, 1993.
[18] Buice, C.U. & Eaton, J.K., "Experimental Investigation of Flow Through an Asymmetric Plane Diffuser," Journal of Fluids Engineering, vol. 122, pp. 433-435, 2000.
[19] Kaltenback H. J., Fatica M., Mittal R., Lund T. S., and Moin P., "Study of the Flow in a Planar Asymmetric Diffuser Using Large Eddy Simulations", J. Fluid Mech., Vol. 390, 1999, pp. 151-185.
[20] Patankar S. V., "Numerical heat transfer and fluid flow", McGraw-Hill, New York, USA, 1983.
[21] Iaccarino G., "Predictions of a turbulent separated flow using commercial CFD codes", Trans. ASME, J. Fluids Engineering, Vol. 123, 2001, pp. 819-828.
[22] DalBello T., "Computational study of separating flow in a planar subsonic diffuser", NASA TM 2005-213894, 2005.
[23] Törnblom O., "Experimental and computational studies of turbulent separating internal flows", Doctoral thesis, KTH Mechanics, Stockholm, Sweden, 2006.