Adaptation of turbulence models to a navier-stokes solver

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2005

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Gürdamar, Emre

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This thesis presents the implementation of several two-equation turbulence models into a finite difference, two- and three-dimensional Navier-Stokes Solver. Theories of turbulence modeling and the historical development of these theories are briefly investigated. Turbulence models that are defined by two partial differential equations, based on k-? and k-? models, having different correlations, constants and boundary conditions are selected to be adapted into the base solver. The basic equations regarding the base Navier-Stokes solver to which the turbulence models are implemented presented by briefly explaining the outputs obtained from the solver. Numerical work regarding the implementation of turbulence models into the base solver is given in steps of non-dimensionalization, transformation of equations into generalized coordinate system, numerical scheme, discretization, boundary and initial conditions and limitations. These sections of implementation are investigated and presented in detail with providing every steps of work accomplished. Certain trial problems are solved and outputs are compared with experimental data. Solutions for fluid flow over flat plate, in free shear, over cylinder and airfoil are demonstrated. Airfoil validation test cases are analyzed in detail. For three dimensional applications, computation of flow over a wing is accomplished and pressure distributions from certain sections are compared with experimental data.

Subject Keywords

Mechanical engineering.

URI

http://etd.lib.metu.edu.tr/upload/12606568/index.pdf
https://hdl.handle.net/11511/15436

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Gürdamar, “Adaptation of turbulence models to a navier-stokes solver,” M.S. - Master of Science, Middle East Technical University, 2005.