Implementation and assessment of Hellsten explicit algebraic Reynolds stress k-omega model

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2022-9

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İlhan, Umut

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Turbulence modeling is one of the most challenging aspects of Computational Fluid Dynamics (CFD). The choice of turbulence model affects the accuracy and computational cost of the CFD analyses. Linear Eddy Viscosity Models (LEVMs) are commonly used in industrial CFD applications due to their low computational cost and ease of convergence. However, they often fail to model complex flow structures. More advanced models, such as Reynolds Stress Transport Models (RSTMs), have better performance for capturing the complex flow physics. RSTMs suffer from convergence difficulties and high computational requirements. In order to combine the computational cost advantage of LEVMs with the accurate prediction of complex flow physics of RSTMs, Explicit Algebraic Reynolds Stress Models (EARSMs) have been introduced. Hellsten utilizes Wallin-Johansson Explicit Algebraic Reynolds Stress Model (WJ-EARSM) as a constitutive model and Menter’s Shear Stress Transport Model as a baseline model for k and ω transport equations. Hellsten slightly modified the transport model equations and calibrated the model coefficients to implement WJ-EARSM on the base turbulence model. This model is claimed to be favorable by having similar computational cost and coding advantages to the SST and a similar level of accuracy to the WJ-EARSM. In this thesis, Hellsten’s k − ω EARSM, which is designed for high-lift aerodynamics, is implemented to open-source CFD code flowPSI. The model is validated using seven different generic turbulence model validation and high-lift aerodynamic test cases.

Subject Keywords

Turbulence, Turbulence model, EARSM, CFD

URI

https://hdl.handle.net/11511/99719

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

U. İlhan, “Implementation and assessment of Hellsten explicit algebraic Reynolds stress k-omega model,” M.S. - Master of Science, Middle East Technical University, 2022.