Comparison of Three Hybrid Turbulence Models for the Flow Around a \(25^{\circ }\) Ahmed Body

  • F. DelassauxEmail author
  • V. Herbert
  • I. Mortazavi
  • C. Ribes
Conference paper
Part of the Notes on Numerical Fluid Mechanics and Multidisciplinary Design book series (NNFM, volume 137)


The flow around the \(25^{\circ }\) Ahmed body has been studied computationally by applying different methods including an improved URANS formulation, the SAS model and two popular hybrid RANS/LES formulations: DDES and SBES models. All of the turbulence models employ the underlying SST RANS formulation. These hybrid models show a good prediction for the drag coefficient, with an error between 0–4% compared to experiments, whereas the discrepancy is slightly more important for the lift coefficient. The DDES model shows the best representation of the flow features between all the models studied.


  1. 1.
    Ahmed, S.R., Ramm, G., Faltin, G.: Some salient features of the time-averaged ground vehicle wake. SAE Technical Paper No. 840300 (1984)Google Scholar
  2. 2.
    ANSYS Fluent Theory Guide, Release 17.0 (2016)Google Scholar
  3. 3.
    Ashton, N., Revell, A.: Key factors in the use of DDES for the flow around a simplified car. Int. J. Heat Fluid Flow 54, 236–249 (2015)Google Scholar
  4. 4.
    Guilmineau, E.: Computational study of flow around a simplified car body. J. Wind Eng. Ind. Aerodyn. 96(6), 1207–1217 (2008)Google Scholar
  5. 5.
    Guilmineau, E., Deng, G., Wackers, J.: Numerical simulation with a DES approach for automotive flows. J. Fluids Struct. 27(5), 807–816 (2011)Google Scholar
  6. 6.
    Haase, W., Aupoix, B., Bunge, U., Schwamborn, D. (eds.): FLOMANIA–A European Initiative on Flow Physics Modelling: Results of the European-Union funded project, 2002–2004, vol. 94. Springer, Science and Business Media (2006)Google Scholar
  7. 7.
    Kapadia, S., Roy, S., Vallero, M., Wurtzler, K., Forsythe, J.: Detached-eddy simulation over a reference Ahmed car model. In: Direct and Large-Eddy Simulation V, pp. 481–488. Springer, Netherlands (2004)Google Scholar
  8. 8.
    Krajnović, S., Davidson, L.: Flow around a simplified car, Part 1: Large eddy simulation. J. Fluids Eng. 127(5), 907–918 (2005)Google Scholar
  9. 9.
    Menter, F.R.: Zonal two equation k-\(\epsilon \) turbulence models for aerodynamic flows. AIAA paper, 2906 (1993)Google Scholar
  10. 10.
    Menter, F.R., Kuntz, M.: Adaptation of eddy-viscosity turbulence models to unsteady separated flow behind vehicles. In: The Aerodynamics of Heavy Vehicles: Trucks, Buses, and Trains, pp. 339–352. Springer, Berlin, Heidelberg (2004)Google Scholar
  11. 11.
    Menter, F.R., Egorov, Y.: The scale-adaptive simulation method for unsteady turbulent flow predictions. Part 1: Theory and model description. Flow Turbul. Combust. 85(1), 113–138 (2010)Google Scholar
  12. 12.
    Minguez, M., Pasquetti, R., Serre, E.: High-order large-eddy simulation of flow over the Ahmed body car model. Phys. Fluids (1994-present) 20(9), 095101 (2008)Google Scholar
  13. 13.
    Rossitto, G., Sicot, C., Ferrand, V., Bore, J., Harambat, F.: Influence of afterbody rounding on the pressure distribution over a fastback vehicle. Exp. Fluids 57(3), 1–12 (2016)Google Scholar
  14. 14.
    Spalart, P.R., Jou, W. H., Strelets, M., Allmaras, S. R.: Comments on the feasibility of LES for wings, and on a hybrid RANS/LES approach. Adv. DNS/LES 1, 4–8 (1997)Google Scholar
  15. 15.
    Spalart, P.R., Deck, S., Shur, M., Squires, K.D., Strelets, M., Travin, A.: A new version of detached-eddy simulation, resistant to ambiguous grid densities. Theor. Comput. Fluid Dyn. 20, 181–195 (2006)Google Scholar

Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • F. Delassaux
    • 1
    Email author
  • V. Herbert
    • 2
  • I. Mortazavi
    • 1
  • C. Ribes
    • 2
  1. 1.Equipe M2N, CNAM ParisParisFrance
  2. 2.Groupe PSAVélizy-VillacoublayFrance

Personalised recommendations