Implementation and assessment of k-omega-gamma transition model for turbulent flows

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2022-5-09

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Karabay, Sami

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The transition from laminar flow to turbulence is challenging to model in CFD. Due to the complex nature of transition, it is neglected in CFD codes usually by assuming the flow is fully turbulent. However, this results in missing the fundamental characteristics of the flow and inaccurate predictions of the flow field. Although there are several transition models, most of them cannot be used in CFD simulations due to practical issues or low accuracy. Yet, some of these models are promising and candidates to be used in CFD simulations. In this study, Menter’s k-omega-gamma transition model is studied and applied to an open-source FlowPsi CFD solver. The main objective is to capture the transition mechanism in CFD simulations. The model is verified using the Klebanoff and ERCOFTAC flat plate cases and several 2D cases. Skin friction coefficient results are compared to experimental data. Results show that k-omega-gamma transition model can predict laminar-to-turbulent transitions accurately.

Subject Keywords

Transitional Flow, Transition Model, Intermittency, CFD, Flat Plate

URI

https://hdl.handle.net/11511/97394

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

S. Karabay, “Implementation and assessment of k-omega-gamma transition model for turbulent flows,” M.S. - Master of Science, Middle East Technical University, 2022.