IMPLEMENTATION, VERIFICATION AND ASSESSMENT OF VORTEX CAPTURING CAPABILITIES OF k-kL TURBULENCE MODEL

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2022-04-01
This study presents the first results of a new turbulence model implementation in our compressible finite volume CFD solver. The k - kL turbulence model is one of the newest two-equation models, and it is based on the ideas of Rotta’s two-equation model. Various research groups progressively develop the model, and it is maturing rapidly. Reports suggest that the k - kL turbulence model provides superior results compared to the other two-equation turbulence models in specific problems. The improved solutions are observed mainly for the flows with high adverse pressure gradients, the blunt-body wakes and jet interactions. We have implemented the k - kL model (with the standard designation of k-kL-MEAH2015) in our solver, and we are testing it rigorously. This paper presents our results on standard turbulence test cases: subsonic flat plate and subsonic wall-mounted bump. The results compare well with the reference study previously presented and published by model developers. The design of the k - kL model prevents excessive production of turbulence and dissipation; hence it preserves vortices significantly better than the other two-equation models. The implemented model is also tested with a transonic fin trailing vortex case to support this statement. Results show that the k-kL model yields considerably better results than the SST turbulence model in cases including vortices.
JOURNAL OF THERMAL SCIENCE AND TECHNOLOGY

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Citation Formats
Ö. U. Baran, “IMPLEMENTATION, VERIFICATION AND ASSESSMENT OF VORTEX CAPTURING CAPABILITIES OF k-kL TURBULENCE MODEL,” JOURNAL OF THERMAL SCIENCE AND TECHNOLOGY, vol. 42, no. 1, pp. 113–122, 2022, Accessed: 00, 2022. [Online]. Available: https://hdl.handle.net/11511/98081.