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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)

Abstract

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.

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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

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