| This thesis presents numerical studies of fluid-structure interaction for cylinder arrays in various configurations in cross flow. The primary objective of the studies is to acquire, through numerical simulations, an improved understanding of fluid-structure interaction of two circular cylinders in cross flow. Three numerical methods including finite element method (FEM), Lattice Boltzmann Method (LBM) and Finite Volume Method (FVM) are applied in this thesis. Some of the numerical results have been validated by experimental visualization using Laser Induced Fluorescence (LIF) method. Six topics are involved in this thesis.; Firstly, laminar flow over two cylinders in tandem has been experimentally and numerically studied. The Reynolds numbers under consideration are 200 and 1000 and the spacing ratios are 2.0, 3.0, 4.0 and 5.0. The computation is mainly carried out by the 2D finite element method.; Secondly, a numerical study of a two-tandem cylinders system in turbulent flow has been attempted using a standard k-epsilon turbulence model plus a modified wall function. The numerical method is 2D finite element method (FEM). Different L/D from 1.5 to 10 are selected to consider the effect of spacing ratio.; Thirdly, two side-by-side cylinders in a cross flow at subcritical Re over a range of T/D ratios have been numerically investigated. The Re range of this study is Re = 8,000∼160,000. The four T/D ratios, T/D = 1.125, 1.5, 2.0 and 3.0, are chosen because the resulting flow regimes are representative of three different proximity effects observed in two side-by-side cylinders.; Fourthly, two side-by-side cylinders with a small control cylinder at the middle symmetric line are studied both experimentally and numerically. The spacing ratios of the two side-by-side cylinders are selected to 1.5 and 2.0, which is within the range of the biased flow.; Fifthly, the flow-structure interaction phenomenon of two staggered elastic cylinders in a cross flow is examined. The calculations are carried out at Re = 200, P/D = 1.5 and theta = 15°∼75° for two rigid cylinders and two elastic cylinders.; Finally, a three-dimensional circular cylinder with end walls in a cross flow is numerically studied at aspect ratios of a = 8, 16 and 24 and Reynolds number of Re = 100 and 300. (Abstract shortened by UMI.)... |
