Implementation of k-epsilon turbulence models in a two dimensional parallel navier-stokes solver on hybrid grids

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2014

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Kalkan, Onur Ozan

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In this thesis, the popular k-ε turbulence model is implemented on a parallel, 2-dimensional, explicit, density-based, finite volume based Navier-Stokes solver works on hybrid grids, HYP2D. Among the other versions available in the open literature, standard version of the k-ε turbulence mode is studied. Launder-Spalding and Chieng-Launder wall functions are adapted to the turbulence model in order to investigate the effects of the strong gradients in the vicinity of the wall on the turbulence. In order to include the low-Reynolds-number effects near the wall Abid’s and Abe-Kondoh-Nagano near wall models are also implemented. Flow over turbulent flat plate and RAE 2822 airfoil are studied for validation of the implementation. After the results show that the implementation is successful according to experimental data and other numerical solutions, NACA 0012 airfoil is simulated at different flow conditions and the effects of turbulence model on the results are discussed. The ability of simulating the turbulent flow with accuracy is acquired to HYP2D solver.

Subject Keywords

Turbulence., K-epsilon., Navier-Stokes equations.

URI

http://etd.lib.metu.edu.tr/upload/12617781/index.pdf
https://hdl.handle.net/11511/23965

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

O. O. Kalkan, “Implementation of k-epsilon turbulence models in a two dimensional parallel navier-stokes solver on hybrid grids,” M.S. - Master of Science, Middle East Technical University, 2014.