Contents
1 Turbulence Simulation 1
1.1 Navier-Stokes equations . . . . 1
1.2 Large Eddy Simulation . . . . 5
1.2.1 SGS modeling . . . . 6
1.2.2 Filtered equations of the motion . . . . 7
1.2.3 Subgrid Scale model . . . . 9
2 Numerical Method 12 2.1 Introduction . . . 12
2.2 Set of equations . . . 13
2.3 Space discretization . . . 15
2.4 Variational Multiscale approach for Large Eddy Simulation . . 21
2.5 Boundary conditions . . . 23
2.6 Time advancing . . . 23
3 Flow around a circular cylinder at Re
D= 3900. Coarse grid 26 3.1 Description of the test case . . . 26
3.2 Results of the simulations . . . 29
4 Simulations on the fine grid 38 4.1 Description of the test case . . . 38
4.1.1 2D Mesh . . . 38
4.1.2 3D Mesh . . . 46
II
4.1.3 Boundary conditions; CFL number; Numerical viscos- ity γ . . . 50 4.2 Results of the simulations . . . 50 4.3 Analysis of the flow fields . . . 58
Bibliography 75
III
