A numerical simulation of steady and unsteady two-dimensional flows past cylinder with dimples based on highly accurate pseudospectral method is the subject of the present thesis. The vorticity-streamfunction formulation of two-dimensional incompressible Navier-Stokes equations with no-slip boundary conditions is used. The system is formulated on a unit disk using curvilinear body fitted coordinate system. Key issues of the curvilinear coordinate transformation are discussed, to show its importance in properly defined node distribution. For the space discretization of the governing system the Fourier-Chebyshev pseudospectral approximation on a unit disk is implemented. To handle the singularity at the pole of the unit disk the approach of defining the computational grid proposed by Fornberg was implemented. Two algorithms for solving steady and unsteady problems are presented. For steady flow simulations the non-linear time-independent Navier-Stokes problem is solved using the Newton's method. For the time-dependent problem the semi-implicit third order Adams-Bashforth/Backward Differentiation scheme is used. In both algorithms the fully coupled system with two no-slip boundary conditions is solved. Finally numerical result for both steady and unsteady solvers are presented. A comparison of results for the smooth cylinder with those from other authors shows good agreement. Spectral accuracy is demonstrated using the steady solver.

Zugl.: München, Techn. Univ., Diss., 2008

Th. univ.--Math.--Paris 6, 1989. / Contient un choix de texte de divers auteurs en français et en anglais. 1989 d'après la déclaration de dépôt légal. Notes bibliogr.

Thesis (M.S.)--University of Toledo, 2010. / Typescript. "Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science degree in Mechanical Engineering." "A thesis entitled"--at head of title. Title from title page of PDF document. Bibliography: p. 51-56.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 92-101). Also available in electronic version.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnologico / Made available in DSpace on 2016-01-08T21:43:50Z (GMT). No. of bitstreams: 1 108908.pdf: 11471875 bytes, checksum: 449720f2e77c215310f2d1ab688d540a (MD5) Previous issue date: 1997 / Esta dissertação descreve, analisa e implementa métodos iterativos da família do Gradiente Conjugado (GC), na solução de sistemas lineares resultantes da discretização das equações de Navier-Stokes (NS) e da equação da condução de calor em malhas não-estruturadas de Voronoi, utilizando o método dos volumes finitos. Descreve-se e adota-se três tipos de ordenações na malha computacional, avaliando o desempenho através de métodos iterativos. Apresenta-se algumas técnicas de pré-condicionamento e implementa-se três delas: diagonal, SSOR e por fatoração de Cholesky incompleta. Estas, aplicadas no método GC e analisadas de acordo com a distribuição dos autovalores. Na discretização das equações de NS são utilizadas três formas distintas de avaliação dos gradientes de pressão, validados no cálculo do escoamento laminar incompressível.

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Orientador : Rakesh Kumar Bhatnagar / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Científica / Made available in DSpace on 2018-07-15T11:45:11Z (GMT). No. of bitstreams: 1 Fiorentini_Dario_M.pdf: 1096751 bytes, checksum: a69fd372f29278812d49b77c6de88c5d (MD5) Previous issue date: 1980 / Resumo: Não informado / Abstract: Not informed / Mestrado / Mestre em Matemática Aplicada

Orientador: Jose Luiz Boldrini / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Científica / Made available in DSpace on 2018-07-19T02:31:13Z (GMT). No. of bitstreams: 1 LorcaPizarro_SebastianAntonio_D.pdf: 1280091 bytes, checksum: 7d515274b16d8ac09d18f4cf718d5213 (MD5) Previous issue date: 1994 / Resumo: Não informado / Abstract: Not informed / Doutorado / Doutor em Matemática

Many interesting problems in classical physics involve the behavior of solutions of nonlinear hyperbolic systems as certain parameter and coefficients becomes infinite. Quite often, the limiting solution (when it exits) satisfies a completely different nonlinear partial differential equation. The incompressible limit of the compressible Navier-Stokes equations is one physical problem involving dissipation when such a singular limiting process is interesting. In this article we study the time-discretized compressible Navier-Stokes equation and consider the incompressible limit as the Mach number tends to zero. For γ-law gas, 1 < γ ≤ 2, D ≤ 4, we show that the solutions (ρ(ε), μ(ε)/ε) of the compressible Navier-Stokes system converge to the solution (1, v) of the incompressible Navier-Stokes system. Furthermore we also prove that the limit also satisfies the Leray energy inequality.