Gas-kinetic methods for 3-d inviscid and viscous flow solutions on unstructured/hybrid grids

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2007

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Ilgaz, Murat

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In this thesis, gas-kinetic methods for inviscid and viscous flow simulations are developed. Initially, the finite volume gas-kinetic methods are investigated for 1-D flows as a preliminary study and are discussed in detail from theoretical and numerical points of view. The preliminary results show that the gas-kinetic methods do not produce any unphysical flow phenomena. Especially the Gas-Kinetic BGK method, which takes into account the particle collisions, predicts compressible flows accurately. The Gas-Kinetic BGK method is then extended for the solution of 2-D and 3-D inviscid and viscous flows on unstructured/hybrid grids. The computations are performed in parallel. Various inviscid and viscous test cases are considered and it is shown that the Gas-Kinetic BGK method predicts both inviscid and viscous flow fields accurately. The implementation of hybrid grids for viscous flows reduces the overall number of grid cells while enabling the resolution of boundary layers. The parallel computations significantly improve the computation time of the Gas-Kinetic BGK method which, in turn, enable the method for the computation of practical aerodynamic flow problems.

Subject Keywords

Aeronautics.

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http://etd.lib.metu.edu.tr/upload/2/12608241/index.pdf
https://hdl.handle.net/11511/17220

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Ilgaz, “Gas-kinetic methods for 3-d inviscid and viscous flow solutions on unstructured/hybrid grids,” Ph.D. - Doctoral Program, Middle East Technical University, 2007.