Implementation and verification of k-kl turbulence model

2021-09-08
Dikbaş, Erdem
Baran, Özgür Uğraş
In this study, we present the first results of a new turbulence model implementation in our compressible finite volume CFD solver. The k − kL turbulence model is based on the ideas of Rotta’s two-equation model. Various research groups progressively develop the model, and it is maturing rapidly. According to the results presented by others, the k − kL turbulence model provides superior results compared to other two-equation turbulence models. The improved solutions are observed especially in flows with high adverse pressure gradients, the blunt body wakes and jet interactions. We have implemented the k − kL model in our solver and we are testing it rigorously. This paper presents our results on standard turbulence test cases, which are subsonic flat plate and subsonic wall-mounted bump. The results compare well with the reference study that are previously presented and published by model developers. The k − kL model prevents excessive production of turbulence and dissipation; hence it preserves vortices significantly better than the other RANS models. Therefore, the implemented model is also tested with a transonic fin trailing vortex case and considerably better results are achieved compared to the SST turbulence model.
11th Ankara International Aerospace Conference

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Citation Formats
E. Dikbaş and Ö. U. Baran, “Implementation and verification of k-kl turbulence model,” presented at the 11th Ankara International Aerospace Conference, Ankara, Türkiye, 2021, Accessed: 00, 2022. [Online]. Available: http://aiac.ae.metu.edu.tr/paper.php?No=AIAC-2021-129.